Part number GL-E223-ADOC 0614
Indirect-Fired Water Heaters
This manual must only be used by a qualified heating installer/service technician. BEFORE installing,
read all instructions in this manual and all other information shipped with the water heater. Perform
steps in the order given. Failure to comply could result in severe personal injury, death or substantial
property damage.
Read important user safety information found on page 3, page 24 and page 25. Installation and
service should only be performed by a qualified service technician. Retain this manual for future reference.
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AQUA PLUS indirect-fired water heaters — Product Manual
Contents
When servicing water heater . . . . . . . . . . . . . . . . . . . . 3
Operating restrictions . . . . . . . . . . . . . . . . . . . . . . . .3
Boiler water restrictions . . . . . . . . . . . . . . . . . . . . . . . 3
Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Code restrictions . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Water heater placement . . . . . . . . . . . . . . . . . . . . . . .4
Install levelling legs . . . . . . . . . . . . . . . . . . . . . . . . . 4
Domestic water piping requirements. . . . . . . . . . . . . . . . 5
Water heater operating restrictions. . . . . . . . . . . . . . . . . 5
Boiler water restrictions . . . . . . . . . . . . . . . . . . . . . . . 5
Hot Water Can Scald! . . . . . . . . . . . . . . . . . . . . . . . . 5
Piping overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Maintaining domestic water temperature in the supply piping . 8
Time delay at fixtures . . . . . . . . . . . . . . . . . . . . . . . . 8
Balancing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Components required . . . . . . . . . . . . . . . . . . . . . . . .8
Connecting to the water heater . . . . . . . . . . . . . . . . . . .8
Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Potential problems . . . . . . . . . . . . . . . . . . . . . . . . . 10
Filling the piping. . . . . . . . . . . . . . . . . . . . . . . . . . 19
Wiring requirements. . . . . . . . . . . . . . . . . . . . . . . . 20
Circulators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Zone Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Wiring to the water heater. . . . . . . . . . . . . . . . . . . . . 20
Wiring options . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Use domestic priority . . . . . . . . . . . . . . . . . . . . . . . 20
Boiler water restrictions . . . . . . . . . . . . . . . . . . . . . . 23
Maximum boiler-side flow rate . . . . . . . . . . . . . . . . . . 23
Filling the domestic water tank . . . . . . . . . . . . . . . . . . 23
Start-up and operation . . . . . . . . . . . . . . . . . . . . . . 23
Start-up checklist . . . . . . . . . . . . . . . . . . . . . . . . . 23
Setting the thermostat . . . . . . . . . . . . . . . . . . . . . . . 24
Hot Water Can Scald! . . . . . . . . . . . . . . . . . . . . . . . 24
ANNUAL start-up by qualified service technician . . . . . . . 25
Inspect anode and water heater interior . . . . . . . . . . . . . 26
Drain the water heater if necessary during shutdown periods . 26
Troubleshooting procedures . . . . . . . . . . . . . . . . . . . 27
Preparation for troubleshooting . . . . . . . . . . . . . . . . . 27
Part number GL-E223-ADOC 0614
2
AQUA PLUS indirect-fired water heaters — Product Manual
Please read before proceeding
Failure to adhere to the guidelines on this page can
result in severe personal injury, death or substantial
property damage.
Read all instructions before installing. Failure to follow all instruc-
tions in proper order can cause severe personal injury, death or
substantial property damage.
When servicing water heater
• To avoid electric shock, disconnect electrical supply before
performing maintenance.
• To avoid severe burns, allow water heater to cool before per-
forming maintenance.
Operating restrictions
• Maximum domestic hot water temperature: residential sizes
— commercial sizes — . Pay attention to the
water temperature warnings throughout this manual.
• Maximum boiler water temperature — 200°F.
• Maximum working pressure for tank — 150 PSIG.
• Water chemistry limits:
• hardness — less than 6 grains/gal.
• pH — above 6 and less than 8.
• chlorides — less than 200 ppm.
Boiler water restrictions
• Thoroughly flush the boiler system (without water heater
connected) to remove sediment.
• The water heater heat exchanger can be damaged by build-up
or corrosion due to sediment.
• Boiler water (including additives) must be practically non-
toxic, having toxicity rating or class of 1, as listed in Clinical
Toxicology of Commercial Products.
• If antifreeze is used in boiler system:
• Local codes may require a backflow preventer on cold
water supply line.
• Use antifreeze specifically intended for hydronic heating
systems. Inhibited propylene glycol is recommended.
• Follow boiler manual instructions for antifreeze usage.
• Do not use automotive, ethylene glycol or petroleum-
based antifreeze. Do not use any undiluted antifreeze.
Location
• This water heater is not intended for outdoor installation.
• Install the water heater so if the tank or any connections
should leak, the water flow will not cause damage to area
near water heater, or to lower floors of structure. When such
locations cannot be avoided, install a suitable drain pan under
water heater. Drain pans are available at your local plumbing
supply store.
• This product is designed for vertical installation only.
When calling or writing about the water
heater — Please have the water heater se-
rial number from the serial number label,
located on the back side of the water
heater, adjacent to the rating plate.
Any claims for damage or shortage in
shipment must be filed immediately
against the transportation company by
the consignee.
The following defined terms are used throughout this
manual to bring attention to the presence of hazards
of various risk levels or to important information
concerning the life of the product.
Indicates presence of hazards that will
cause severe personal injury, death or
substantial property damage.
Indicates presence of hazards that can
cause severe personal injury, death or
substantial property damage.
Indicates presence of hazards that will
or can cause minor personal injury or
property damage.
Indicates special instructions on installa-
tion, operation or maintenance that are
important but not related to personal
injury or property damage.
This manual provides installation and
operation guidelines for Weil-McLain
AQUA PLUS indirect water heaters.
The installer is responsible for ensuring
that the installation complies with this
manual, the boiler manual and all ap-
plicable codes.
— The
water heater must be installed by a li-
censed plumber. The installation must
follow all Massachusetts code require-
ments. The domestic water piping must
comply with the piping shown in this
manual. See “Domestic water piping,”
page 6, for details and code requirements.
Part number GL-E223-ADOC 0614
3
AQUA PLUS indirect-fired water heaters — Product Manual
Pre-installation
Clearance recommendations
Codes
1. Installation must conform with instructions in this
manual and, where applicable:
• local, state, provincial, and national codes, laws,
regulations and ordinances.
• in Canada — B149.1 or B149.2 Installation
Code.
2. AQUA PLUS water heaters are exempt from ASME
Section VIII, Division 1 Code construction per In-
terpretation VIII-1-86-136. Check with local codes
for applicability.
3. Where recommendations in this manual differ from
local or national codes, local or national codes take
precedence.
Code restrictions
1. Single-wall heat exchanger in water heater complies
with National Standard Plumbing Code, provided
that:
a. boiler water (including additives) is practically
non-toxic, having toxicity rating or class of 1,
as listed in Clinical Toxicology of Commercial
Products, and
b. boiler water pressure is limited to maximum 30
PSIG by approved relief valve.
1. Single-wall heat exchangers are permitted if they
satisfy all of the following requirements —
a. The heat transfer medium is potable water or
contains only substances which are recognized
as safe by the U. S. Food and Drug Adminis-
tration.
b. The pressure of the heat transfer medium is
maintained less than the normal minimum op-
erating pressure of the potable water system.
c. Exception: Steam complying with #a, above.
d. The equipment is permanently labeled to
indicate that only additives recognized as safe
by the FDA shall be used in the heat transfer
medium.
2. Other heat exchanger designs may be permitted
where approved by the Administrative Authority.
Recommended clearances
Installation location must provide adequate clearances for servicing and
proper operation of the water heater. See Figure 1.
• 1” clearance is permissible to either side of water heater, but the Instruc-
tion label or other labels may be hidden.
• Top (vertical) clearance is 12” minimum.
• Refer to boiler manual for boiler clearances.
Clearance to combustible materials
1. Provide at least ½” clearance between all hot water pipes and combus-
tible materials.
Water heater placement
1. Read and comply with “Location,” page 3 of this manual.
2. Select a convenient location for the water heater, based on domestic
and boiler piping hook-ups.
3. Keeping the distance between boiler and water heater short will:
• reduce piping heat loss.
• provide minimum friction loss.
Install levelling legs
1. Carefully tip the water heater onto its side.
2. Screw the four levelling legs into the base.
3. Return the water heater to the upright position and set in place.
4. Adjust the legs as necessary to level the water heater.
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Pre-installation
(continued)
Hot Water Can Scald!
• Water heated to temperature for clothes washing,
dish washing and other sanitizing needs can scald
and cause permanent injury.
• Children, elderly, and infirm or physically handi-
capped persons are more likely to be permanently
injured by hot water. Never leave them unattended
in bathtub or shower. Never allow small children to
use a hot water tap or draw their own bath.
• If anyone using hot water in the building fits
the above description, or if state laws or local
codes require certain water temperatures at
hot water taps, you must take special precau-
tions:
• Use lowest possible temperature setting.
• Install some type of tempering device, such
as an automatic mixing valve, at hot water
tap or water heater. Automatic mixing valve
must be selected and installed according
to valve manufacturer’s recommendations
and instructions.
• Water passing out of drain valves may be extremely
hot. To avoid injury:
• Make sure all connections are tight.
• Direct water flow away from any person.
Domestic water piping requirements
1. Install unions on all piping for easy removal of water heater.
2. Use
to protect hot and cold water
fittings from corrosion when connecting dissimilar materials such
as copper and galvanized iron pipe.
3.
, install a
pressure reducing valve on cold water supply line to prevent water
loss through T&P relief valve. A thermal expansion tank is also
required.
4. If the water heater will replace a tankless coil in the boiler, discon-
nect piping to coil or remove coil from boiler and replace with
a cover plate. Allow water to drain from coil. plug the
tankless coil.
Plugging tankless coil inlet and outlet will result in severe
personal injury, death or substantial property damage.
Studies have indicated that dangerous bacteria,
including
, can form in
the potable water distribution system if certain
minimum water temperatures are not maintained.
Contact your local health department for more
information.
Water heater operating restrictions
1. Read the operating limits under “Operating restrictions,” page 3.
— The water heater is equipped with
a magnesium sacrificial anode. The anode may erode over
time, and should be inspected at least once annually, only
by a qualified service technician. For installations with
a likelihood of poor water conditions, the anode should
be inspected at least every six months. Failure to comply
could result in loss of protection by the anode, causing
possible severe personal injury, death or substantial
property damage due to water heater leakage.
The domestic water chloride concentration must not ex-
ceed 200 ppm. High chloride concentrations can rapidly
disintegrate the water heater’s protective anode.
Boiler water restrictions
1. Read the WARNINGS under “Boiler water restrictions,” page 3.
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Domestic water piping
DHW piping
Piping overview
— If a
backflow preventer, check valve, or pres-
sure reducing valve is piped on cold water
inlet of water heater, you must install an
expansion tank on cold water supply line
to prevent normal thermal expansion
from repeatedly forcing open T&P relief
valve.
The T&P relief valve is not intended for
constant duty, such as relief of pressure
due to repeated normal system expan-
sion. Refer to expansion tank manufac-
turer’s instructions for proper sizing.
Failure to comply could result in severe
personal injury, death or substantial
property damage.
1. Figure 2 — This piping configuration can be used in
most cases, except where local codes require special
components or piping not illustrated.
2. Some codes may require the items listed as optional,
such as a vacuum breaker on the inlet line, or re-
circulation piping.
1. For applications, or as
required elsewhere by local codes, install the fol-
lowing options.
a. Thermal siphon on DHW inlet and outlet.
b. Vacuum breaker on domestic water inlet line.
c. Recirculation — applica-
tions require recirculation piping or heat-traced
piping if the distance from the water heater to
the furthest fixture exceeds 100 feet. See page 8
for details.
Piping connection sizes
(inches NPT)
DHW
in/out
Boiler water
in/out
Recirculation
tapping
¾ 1 ¾
¾ 1 ¾
¾ 1 ¾
1 1 ¾
1 1 ¾
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Domestic water piping
(continued)
LEGEND for Figure 2, page 6
Domestic water supplied to fixtures that could pose
an injury hazard due to high temperature, such as
showers and faucets, should be equipped with a
temperature regulating device, such as an
.
When the supply pressure is higher than 70 PSIG,
install a
on cold water
supply line to prevent water loss through T&P relief
valve. A thermal expansion tank is also required.
This symbol, where used in this manual, indicates the
item is required by Massachusetts code.
This symbol indicates the item is optional, unless
required by applicable codes.
1
Domestic cold water inlet connection — see Fig-
ure3,page6 for size
2 Domestic hot water outlet connection — see Fig-
ure3,page6 for size
3 Domestic recirculation connection — unused
4 Boiler water inlet to coil — see Figure3,page6 for size
5 Boiler water outlet from coil — see Figure3,page6 for
size
6 Drain valve — provided by installer
• Install a drain valve on the DHW inlet to the water heater
as shown.
7
Piping from drain valve
• Pipe from drain to floor drain, if available.
8
T&P valve connection
9 T&P relief valve — supplied with water heater
• Use only the T&P valve supplied with the water heater.
See Replacement parts for part number.
• Install the T&P relief valve in the top center tapping, as
shown.
10
T&P relief valve discharge piping —
• must be made of material serviceable for temperatures
of 250°F or greater.
• must be directed so that hot water flows away from all
persons.
• must be directed to a suitable place for disposal.
• must be installed so as to allow complete draining of the
T&P relief valve and discharge line.
• must NOT be excessively long — using more than 2 el-
bows or 15 feet of piping can reduce discharge capacity.
• must NOT be directly connected to a drain — terminate
discharge piping within 6” from floor — refer to local
codes.
• must NOT be plugged, reduced or restricted.
• must NOT be subjected to freezing.
Do not install any valve between T&P relief valve and
tank connection, or on T&P relief valve discharge
piping. Do not plug T&P relief valve or its discharge
piping. Improper placement and piping of T&P re-
lief valve can cause severe personal injury, death or
substantial property damage.
11
Temperature adjustment knob
12 Anode access
• The anode is specially made for this water heater. Use
only the anode available from Weil-McLain, as listed in
Replacement parts.
13
Mixing valve — —
• See Replacement parts for thermostatic mixing valves
available from Weil-McLain.
14
Domestic cold water supply
When the water supply pressure is higher than
70 PSIG, install a pressure-reducing valve on the
cold water supply line to prevent leakage from the
T & P relief valve. A thermal expansion tank is also
required.
15
Domestic mixed-temperature water supply to
system
(when used — requires mixing valve)
16 Domestic high-temperature hot water supply to
system
17 Heat trap loops (12” minimum) —
18 Isolation valves
19 Thermal expansion tank —
• if cold water line is equipped with a backflow
preventer or pressure reducing valve — see
on page 6.
20
Shock arrester —
Dishwashers, clothes washers, and fast-closing positive
shutoff valves incorporated in the system all contrib-
ute to creating water shock. Install a water hammer
arrester to prevent damage to pipes and appliances.
See control manufacturer’s instructions for applica-
tion and installation.
21
Unions
• Use dielectric unions or couplings to protect hot and cold
water fittings from corrosion when connecting dissimilar
materials such as copper and galvanized iron pipe.
22
Backflow preventer — — — (required
for Commonwealth of Massachusetts)
23 Vacuum breaker —
24 Pressure reducing valve —
• when the supply pressure is higher than
70 PSIG — A thermal expansion tank is also required.
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Recirculation
applications require recircu-
lation piping or heat-traced piping if the distance
from the water heater to the furthest fixture exceeds
100 feet.
Maintaining domestic water
temperature in the supply piping
1. Recirculation is used to reduce wait time for water use, to
minimize hot water and energy waste caused during the
waiting period, and to prevent degradation of the system
supply water temperature. ASPE recommends recirculation
when the distance from the water heater to the furthest fix-
ture exceeds 100 feet or the time lag for hot water to reach a
fixture(s) exceeds 30 seconds.
2. Consult local codes and American Society of Plumbing
Engineers (ASPE) Domestic Water Heating Design Manual,
1998, for further information.
Time delay at fixtures
1. Figure 5, page 9 is from the ASPE Domestic Water Heating
Design Manual, 1998. It shows the time required for usable
hot water to arrive at a fixture based on the fixture flow rate
(available from industry and manufacturer’s data) and the
length and diameter of the dead-end branch pipe supplying
the fixture.
2. The time lag should generally not exceed 30 seconds.
3. For residential and office applications, the owner may prefer
a limit of 10 seconds.
4. You can use Figure 5 as a guide to determining the location
of circulation return lines relative to fixtures.
Balancing
1. When multiple branches are connected to the supply pip-
ing, each branch must be connected to the recirculation
system.
a. At each of these connections to the return piping, install
shutoff valves, a flow metering device, check valve and a
strainer as shown in Figure 4, page 9.
b. Check local codes for specific installation require-
ments.
2. These branches must be balanced to prevent pipe erosion
and unacceptable time delays at some fixtures.
3. Balancing options include circuit setters, memory stop valves
or factory preset devices (with flow metering provision in
the piping).
Components required
1. For residential applications, consult circulator manufacturer’s
data for circulator selection and additional components
required.
2. On most commercial systems, install the devices shown in
Figure 4, page 9, and any other devices or piping methods
required by local codes.
a. The check valves are required to prevent fixtures from
taking hot water through the return lines.
b. Shutoff valves are needed to allow cleaning and replacing
balancing devices.
c. Include strainers to remove sediment which could
damage the circulator and / or affect the flow balancing
devices.
3. Size the circulator and piping based on the temperature drop
allowed between the water available at the water heater and
the water delivered at the fixture.
a. The return piping will almost always be smaller than the
supply piping, but should never be smaller than ½” to
prevent problems with the circulator.
4. Make provision for removal of air in all return lines. Where
the returns cannot be vented by topmost fixtures in the
system, install automatic air venting at the top of the return
piping.
Connecting to the water heater
1. Install the domestic water components as shown in Fig-
ure 2, page 6.
2. See Figure 6, page 10 for the piping required to the water
heater.
— Continued on page 10 —
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Recirculation
(continued)
Part number GL-E223-ADOC 0614
9
Copper pipe ½” 25 63 8 21 5 13 3 8
¾” 48 119 16 40 10 24 6 15
Steel pipe ½” 63 157 21 52 13 31 8 20
¾” 91 228 30 76 18 46 11 28
CPVC pipe ½” 64 159 21 53 13 62 8 20
¾” 95 238 32 79 19 48 12 30
NOTE: Select branch size and length for less than 31 seconds delay.
Recirculation components
Time lag to obtain hot water at fixture for branch lengths of 10 and 25 feet (ASPE
Domestic Water Heating Design Manual)
AQUA PLUS indirect-fired water heaters — Product Manual
Recirculation
(continued)
Components
1. Little flow is required to maintain a temperature
in the piping.
2. Size of circulator depends on minimum flow re-
quirements of the tempering valve.
3. Minimum flow rates of the tempering valve must
be maintained.
1. Used to control the on-off position of the circula-
tor. Aquastat is set 5° to 10° lower than mixed water
outlet of the mixing valve (#7).
2. The circulator cannot run continuously as bypass
through the mixing valve will eventually allow the
temperature on the piping to climb to the water
heater temperature during draw periods.
1. Assure the flow of water in one direction.
2. Each check valve functions as follows:
a. #3 and #4 prevent bypass in the event of pres-
sure drop.
b. #5 prevents thermal siphoning of hot water to
the cold water supply.
c. #6 prevents flow of cold water to the tempered
water supply. A draw of tempered water will
not result in flow of cold water into the return
loop.
Operation
1. During period of normal use (fixtures on) — Cir-
culator is off. There is no flow through #6, there is
flow through #5 equal to the flow at the fixtures,
there is flow through #3 and/or #4 equal to flow
at fixture.
2. When all fixtures are off — Circulator is off. There is
no flow through #3, #4, #5 or #6. Water temperature
in piping is cooling.
3. When temperature at aquastat #2 falls 10° below
temperature to be maintained — Circulator is on.
There is flow through #6 equal to the minimum
required by the mixing valve, flow through #3 and
#4 equals the flow of the circulator. There is no
flow through #5.
4. Aquastat reaches temperature — Circulator is off.
There is no flow through #3, #4, #5 or #6.
Recirculation piping
Potential problems
1. Missing check valves #3 or #4 — Extreme pressure drop can cause
reverse flow of water; hot to cold supply or cold to hot supply.
2. Missing check valve #5 — Hot water can migrate from the water heater
back through the cold water supply.
3. Missing check valve #6 — Cold water can be forced back through the
tempered water supply when a fixture is opened.
4. No aquastat #2 — Circulator runs continuously. Small amount of
water will pass through mixing valve. Eventually all hot water is flow-
ing through valve. Recirculated water through cold port, hot water
through hot port.
5. Circulator too small — Mixing valve performance erratic.
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Zoning with circulators — direct-connected system piping
Notes
• Place circulators at begin-
nings of zones. Placing
them at the ends of zones
could result in heating idle
zones.
• Size manifold piping for
total flow of all zone cir-
culators.
• Locate flow / check valves
as close as possible to water
heater boiler side connec-
tions — to reduce heat loss
between cycles.
Wiring
• WMCR zone controller,
optional priority — Fig-
ure 18, page 21.
1. This drawing is conceptual
only. It shows representa-
tive piping components
and layout. Weil-McLain
does not represent that this
drawing meets any partic-
ular mechanical or build-
ing codes. The installer is
responsible for inclusion
of all required safety de-
vices, or other miscella-
neous piping hardware not
shown on drawing. The
installer is responsible for
proper sizing / selection of
all hardware shown on this
diagram.
2. See boiler manual for spe-
cific details on installing
the boiler.
:
apply the drawings in this
manual. Refer only to the boiler
manual.
Heater
model
GPM
Pipe
size
Heater
model
GPM
Pipe
size
8 1”
14 1¼” *
8 1”
14 1¼” *
8 1”
Requires 1¼”x1” reducers at water heater
Boiler-side piping
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Boiler-side piping
(continued)
Zoning with circulators — primary/secondary system piping
Notes
• Place circulators at begin-
nings of zones. Placing
them at the ends of zones
could result in heating idle
zones.
• Size manifold piping for
total flow of all zone cir-
culators.
• Locate flow / check valves
as close as possible to water
heater boiler side connec-
tions — to reduce heat loss
between cycles.
Wiring
• WMCR zone control-
ler, optional priority —
Figure 18, page 21.
1. This drawing is conceptual
only. It shows representa-
tive piping components
and layout. Weil-McLain
does not represent that this
drawing meets any partic-
ular mechanical or build-
ing codes. The installer is
responsible for inclusion
of all required safety de-
vices, or other miscella-
neous piping hardware not
shown on drawing. The
installer is responsible for
proper sizing / selection of
all hardware shown on this
diagram.
2. See boiler manual for spe-
cific details on installing
the boiler.
Part number GL-E223-ADOC 0614
12
:
apply the drawings in this
manual. Refer only to the boiler
manual.
Recommended ow rate and minimum boiler-side pipe size
Heater
model
GPM
Pipe
size
Heater
model
GPM
Pipe
size
8 1”
14 1¼” *
8 1”
14 1¼” *
8 1”
Requires 1¼”x1” reducers at water heater
AQUA PLUS indirect-fired water heaters — Product Manual
Boiler-side piping
(continued)
Zoning with zone valves — direct-connected system piping
Notes
• Place circulators at begin-
nings of zones. Placing
them at the ends of zones
could result in heating idle
zones.
• Size manifold piping for
total flow of all zone cir-
culators.
• Locate flow / check valves
as close as possible to water
heater boiler side connec-
tions — to reduce heat loss
between cycles.
Wiring
• WMZV zone control-
ler, optional priority —
Figure 19, page 22.
1. This drawing is conceptual
only. It shows representa-
tive piping components
and layout. Weil-McLain
does not represent that this
drawing meets any partic-
ular mechanical or build-
ing codes. The installer is
responsible for inclusion
of all required safety de-
vices, or other miscella-
neous piping hardware not
shown on drawing. The
installer is responsible for
proper sizing / selection of
all hardware shown on this
diagram.
2. See boiler manual for spe-
cific details on installing
the boiler.
Part number GL-E223-ADOC 0614
13
:
apply the drawings in this
manual. Refer only to the boiler
manual.
Recommended ow rate and minimum boiler-side pipe size
Heater
model
GPM
Pipe
size
Heater
model
GPM
Pipe
size
8 1”
14 1¼” *
8 1”
14 1¼” *
8 1”
Requires 1¼”x1” reducers at water heater
AQUA PLUS indirect-fired water heaters — Product Manual
Boiler-side piping
(continued)
Zoning with zone valves — primary/secondary system piping
Notes
• Place circulators at begin-
nings of zones. Placing
them at the ends of zones
could result in heating idle
zones.
• Size primary piping for
total flow of all zone cir-
culators.
• Locate flow / check valves
as close as possible to water
heater boiler side connec-
tions — to reduce heat loss
between cycles.
Wiring
• WMZV zone controller,
optional priority — Fig-
ure 19, page 22.
1. This drawing is conceptual
only. It shows representa-
tive piping components
and layout. Weil-McLain
does not represent that this
drawing meets any partic-
ular mechanical or build-
ing codes. The installer is
responsible for inclusion
of all required safety de-
vices, or other miscella-
neous piping hardware not
shown on drawing. The
installer is responsible for
proper sizing / selection of
all hardware shown on this
diagram.
2. See Boiler Manual for spe-
cific details on installing
the boiler.
Part number GL-E223-ADOC 0614
14
:
apply the drawings in this
manual. Refer only to the boiler
manual.
Recommended ow rate and minimum boiler-side pipe size
Heater
model
GPM
Pipe
size
Heater
model
GPM
Pipe
size
8 1”
14 1¼” *
8 1”
14 1¼” *
8 1”
Requires 1¼”x1” reducers at water heater
AQUA PLUS indirect-fired water heaters — Product Manual
Boiler-side piping
(continued)
Dedicated single-boiler piping
Notes
• Place circulators at begin-
nings of zones. Placing
them at the ends of zones
could result in heating idle
zones.
• Size manifold piping for
total flow of all zone cir-
culators.
• Locate flow / check valves
as close as possible to water
heater boiler side connec-
tions — to reduce heat loss
between cycles.
Wiring
• Connect water heater ther-
mostat wires to boiler’s
T-T terminals or heat de-
mand connection.
1. This drawing is conceptual
only. It shows representa-
tive piping components
and layout. Weil-McLain
does not represent that this
drawing meets any partic-
ular mechanical or build-
ing codes. The installer is
responsible for inclusion
of all required safety de-
vices, or other miscella-
neous piping hardware not
shown on drawing. The
installer is responsible for
proper sizing / selection of
all hardware shown on this
diagram.
2. See boiler manual for spe-
cific details on installing
the boiler.
Part number GL-E223-ADOC 0614
15
:
apply the drawings in this
manual. Refer only to the boiler
manual.
Recommended ow rate and minimum boiler-side pipe size
Heater
model
GPM
Pipe
size
Heater
model
GPM
Pipe
size
8 1”
14 1¼” *
8 1”
14 1¼” *
8 1”
Requires 1¼”x1” reducers at water heater
AQUA PLUS indirect-fired water heaters — Product Manual
Boiler-side piping
(continued)
Multiple water heaters — domestic water piping
Alternate methods of revers-return piping and Easy-Fit® Manifold detail
Failure to install automatic
mixing valve where recom-
mended can result in severe
personal injury or death.
1. This drawing is conceptual
only. It shows representa-
tive piping components
and layout. Weil-McLain
does not represent that this
drawing meets any partic-
ular mechanical or build-
ing codes. The installer is
responsible for inclusion
of all required safety de-
vices, or other miscella-
neous piping hardware not
shown on drawing. The
installer is responsible for
proper sizing / selection of
all hardware shown on this
diagram.
2. Wire water heater thermo-
stats in series when con-
necting to boiler controller
or boiler T-T terminals.
3. Install automatic mixing
valve at either the system
hot water connection or
at each water heater.
4. See page 8 through page 10
for additional recircula-
tion information and pip-
ing details.
Part number GL-E223-ADOC 0614
16
AQUA PLUS indirect-fired water heaters — Product Manual
Boiler-side piping
(continued)
Multiple water heaters and dedicated multiple boilers — boiler water piping
Notes
• See legend and details in
Figure 12, page 16.
1. This drawing is conceptual
only. It shows representa-
tive piping components
and layout. Weil-McLain
does not represent that this
drawing meets any partic-
ular mechanical or build-
ing codes. The installer is
responsible for inclusion
of all required safety de-
vices, or other miscella-
neous piping hardware not
shown on drawing. The
installer is responsible for
proper sizing / selection of
all hardware shown on this
diagram.
2. See boiler manual for spe-
cific details on installing
the boiler.
:
apply the drawings in this manual. Refer only to the boiler manual.
Part number GL-E223-ADOC 0614
17
AQUA PLUS indirect-fired water heaters — Product Manual
Connecting to a low-pressure steam boiler
Special considerations
When designing steam and domestic hot water systems, there are some
key issues that must be taken into consideration during the initial de-
sign phase. By designing the system properly from the start, you can
avoid problems and have a hot water loop in a steam boiler system.
• The domestic water demand should preferably not exceed 1/3
of the steam boiler capacity. Larger demand may cause difficulty
obtaining steam as needed.
• Keep the loop temperature below the flash point. Flashing can result
in noise and circulator damage or shortened life.
• Be sure the loop is completely closed, with no automatic or manual
air vents, or anything that could allow air to enter the system when
the pump shuts off.
• Pipe supply from one side of the boiler, return to the opposite
side as shown.
• Supply from a tapping that is high enough to prevent introducing
sediment into the piping and circulator yet still below the water
line. Avoid the mud leg of the boiler.
• Use an all bronze circulator.
• Avoid wet rotor circulators. Select a circulator with a large
volute, such as a typical 3-piece circulator.
• This will reduce clogging and will resist the corrosion potential
from the steam condensate.
• Make sure the circulator is properly sized. If the circulator runs too
far out on its curve, cavitation potential increases significantly.
• Use (2) flow / check valves as shown to reduce the potential for
gravity circulation.
• DO NOT use spring-loaded check valves in place of the
flow / check valves shown in Figure 16, page 19.
Installation and start-up of water heaters
connected to steam boilers
1. See Figure 16, page 19, for suggested piping schematic.
2. Pipe the domestic water connections to the water heater per “Do-
mestic water piping,” page 6.
Boiler connections for the water heater must be below
the water line. DO NOT use the gauge glass tapping or a
low water cut-off tapping if a LWCO is installed there.
For steam piping, refer to the steam boiler manual.
DO NOT install an air vent anywhere in the piping. The
piping must be air tight.
3. Wire the water heater and circulator to the boiler per suggested
wiring in Figure 15. The water heater must be wired and ready to
operate before proceeding. Note that the L4006A aquastat is located
in the boiler and sets a boiler operating temperature when there is
no call for steam heating.
To fill the boiler and water heater:
1. Follow the procedure given in Figure 16, page 19 to fill the water
heater piping.
2. Follow the boiler manual instructions to fill the steam boiler.
Typical wiring for connection to low-
pressure steam boiler
Valve 7, the memory stop valve, must
be supplied, piped and adjusted as in-
structed. This valve allows cooler return
water to mix with the hot water from
the steam boiler. The valve is set to yield
approximately 180°F water entering the
circulator. Higher temperature water
could cause cavitation in the circulator,
damaging the impeller and shortening
circulator life.
DO NOT connect the piping to the boil-
er’s mud leg. This would probably cause
excessive sediment to enter the water
heater piping, damaging the circulator.
The strainer in the circulator suction line
must be serviced regularly. NOTE that
noise from the circulator is a likely sign
that the strainer is restricting circulator
flow, causing cavitation.
Part number GL-E223-ADOC 0614
18
AQUA PLUS indirect-fired water heaters — Product Manual
Connecting to a low-pressure steam boiler
(continued)
Low pressure steam boiler application — Domestic water heating using water pumped from steam boiler
Notes
• Locate flow / check valve as
close as possible to water
heater boiler side connec-
tions — to reduce heat loss
between cycles.
Use memory stop valve 7 to
blend some of the water re-
turning to the boiler with the
hot water coming from the
boiler. This will reduce the
possibility of flashing (cavita-
tion) in the circulator. Slowly
open valve 7 until temperature
gauge 8 reads 200°F.
Set the memory stop on valve 7
after adjusting. Attach a tag to
the valve warning no to close
or change valve position.
NOTE —
1. This drawing is conceptual
only. It shows representa-
tive piping components
and layout. Weil-McLain
does not represent that this
drawing meets any partic-
ular mechanical or build-
ing codes. The installer is
responsible for inclusion
of all required safety de-
vices, or other miscella-
neous piping hardware not
shown on drawing. The
installer is responsible for
proper sizing / selection of
all hardware shown on this
diagram.
2. See boiler manual for spe-
cific details on installing
the boiler.
Filling the piping
1. Parts of the boiler water piping to the
water heater may be higher than the wa-
ter line, depending on the height of the
water heater boiler supply connection.
The piping must be air tight to prevent air
from pocketing at the top of the piping,
stopping flow.
2. The boiler MUST be filled and ready to
operate before proceeding. Follow the
boiler manual to fill the boiler.
3. Follow the procedure below to fill the
boiler-to-water heater piping. See Fig-
ure 16.
Close isolation valves 5 and 6 to isolate
the boiler.
Close valve 3 and open valve 4. Con-
nect a cold water supply hose to
valve 3. Connect a hose from valve 4
to a drainable location.
Close valve 10. Open valve 7.
Open valve 3. Water will flow through
valve 7 and out through valve 4 to
drain. Open valve 11. Let water run
until all air has been removed from
the line through valve 11. Close valve
11. Close valve 4. Then close valve 3.
Close valve 7. Then open valve 10.
Open valve 3. Water will flow through
the circulator line, the water heater
coil and the return piping, then out
through valve 4 to drain. Let water run
until all air has been removed from the
line. Close valve 4. Then close valve 3.
Remove hoses.
Follow the instructions in “Water
heater filling and start-up,” page 23,
to fill the domestic water side of the
water heater.
Open valve 7 about ¼ turn for an
initial setting.
Open isolation valves 5 and 6. Make
sure the boiler water level is correct
per the boiler manual.
Start the boiler per instructions given
in the boiler manual. Allow boiler to
begin steaming.
Start the DHW circulator. Watch the
temperature at gauge 8. Adjust valve 7
until gauge 8 reads about 180°F with
system at steady operation.
Continue checking under varying
DHW demand conditions to ensure
system will operate as required.
Part number GL-E223-ADOC 0614
19
AQUA PLUS indirect-fired water heaters — Product Manual
Boiler-side wiring and controls
— Can cause severe personal
injury, death or substantial property damage. Disconnect
power before installing and / or servicing.
Wiring requirements
1. All wiring must be a minimum of 18 gauge and installed in accordance
with:
• U.S.A. — National Electrical Code and any other national, state or
local code requirements having jurisdiction.
• Canada — CSA C22.1 Canadian Electrical Code Part 1 and any
other national, provincial and local code requirements having
jurisdiction.
2. If original wire as supplied with appliance must be replaced, Type 90°
C or its equivalent must be used.
3. Refer to control component instructions packed with boiler for ap-
plication information.
4. An optional service switch may be installed in water heater electri-
cal circuit. This switch would only shut off the water heater, not the
home heating system. Do not shut off water heater if there is a chance
of freezing.
5. All electrical contacts are shown with no power applied — off-the-
shelf condition.
Circulators
1. Size priority relay for total amp draw of all circulators.
Zone Valves
1. Size transformer for maximum load of all zone valves.
Wiring to the water heater
1. Field connections to the water heater thermostat are for 24 VAC only,
connecting to the two-pole terminal block shown in Figure 17.
Wiring options
1. This manual shows wiring only for use of Weil-McLain WMCR Cir-
culator Zone Controller or Weil-McLain WMZV Zone Valve Zone
Controller.
2. Other wiring methods may be acceptable and are left to the installer.
Use domestic priority
1. When possible, set controls to provide domestic
priority — that is, on a call for domestic water
the control switches from space heating to DHW
only.
2. Domestic priority ensures the fastest possible re-
sponse to the DHW call for heat.
3. The smaller the water heater, the greater the need
for rapid response.
Inspection hatch assembly (hatch
cover shown transparent)
Temperature adjustment knob
Inspection plate (handhole)
Factory wires from thermostat to field wiring terminal
block
Field wiring terminal block
M8 hex nut
Inspection plate bracket
Part number GL-E223-ADOC 0614
20
AQUA PLUS indirect-fired water heaters — Product Manual
Wiring — zoning with circulators
Notes
• Also refer to the WMCR
manual and Weil-McLain
Boiler Zone Wiring Guide
for further details.
• Refer to Wiring require-
ments on page 20.
System piping
• Figure 7, page 11
• Figure 8, page 12
1. This drawing is conceptual
only. It shows representa-
tive components and wir-
ing. Weil-McLain does not
represent that this drawing
meets any particular me-
chanical or building codes.
The installer is respon-
sible for inclusion of all
required safety devices, or
other miscellaneous pip-
ing hardware not shown
on drawing. The installer
is responsible for proper
sizing / selection of all
hardware shown on this
diagram.
2. Follow component manu-
facturer’s instructions for
installation of all items
shown.
3. See boiler manual for spe-
cific details on installing
the boiler.
Typical wiring — zoning with circulators — DHW priority with Weil-McLain WMCR Circulator Zone Controller
:
apply the drawings in this manual. Refer only to the boiler manual.
Part number GL-E223-ADOC 0614
21
AQUA PLUS indirect-fired water heaters — Product Manual
Wiring — zoning with zone valves
Notes
• Also refer to the WMZV
manual and Weil-McLain
Boiler Zone Wiring Guide
for further details.
• Refer to Wiring require-
ments on page 20.
System piping
• Figure 9, page 13
• Figure 10, page 14
Install all zone valves per valve
manufacturer’s instructions.
1. This drawing is conceptual
only. It shows representa-
tive components and wir-
ing. Weil-McLain does not
represent that this drawing
meets any particular me-
chanical or building codes.
The installer is respon-
sible for inclusion of all
required safety devices, or
other miscellaneous pip-
ing hardware not shown
on drawing. The installer
is responsible for proper
sizing / selection of all
hardware shown on this
diagram.
2. Follow component manu-
facturer’s instructions for
installation of all items
shown.
3. See boiler manual for spe-
cific details on installing
the boiler.
Typical wiring — zoning with zone valves — DHW priority with Weil-McLain WMZV Zone Valve Zone Controller
:
apply the drawings in this manual. Refer only to the boiler manual.
Part number GL-E223-ADOC 0614
22
AQUA PLUS indirect-fired water heaters — Product Manual
Water heater filling and start-up
The installation and water chemistry must meet the
requirements below. Failure to comply could result in
damage to the water heater, causing possible severe
personal injury, death or substantial property damage.
Boiler water restrictions
• Thoroughly flush the boiler system (without water heater con-
nected) to remove sediment.
• The water heater heat exchanger can be damaged by build-up or
corrosion due to sediment.
• Boiler water (including additives) must be practically non-toxic,
having toxicity rating or class of 1, as listed in Clinical Toxicology
of Commercial Products.
• If antifreeze is used in boiler system:
• Local codes may require a backflow preventer on cold water
supply line.
• Use antifreeze specifically intended for hydronic heating sys-
tems. Inhibited propylene glycol is recommended.
• Follow boiler manual instructions for antifreeze usage.
• Do not use automotive, ethylene glycol or petroleum-based
antifreeze. Do not use any undiluted antifreeze.
Maximum boiler-side flow rate
• Select the boiler-side circulator carefully. The flow rate through the
boiler side of the water heater must not exceed the values below.
Higher flow rates could result in an input above the rating of the
T&P valve.
•
•
Filling the domestic water tank
1. Fill the domestic water tank with fresh water that meets the chemistry
requirements above.
2. Do not exceed a fill pressure of 70 PSIG.
When the water supply pressure is higher than 70 PSIG, make
sure that a pressure-reducing valve is installed on the cold
water supply line to prevent leakage from the T&P relief valve.
A thermal expansion tank is also required.
3. Vent the piping as necessary to remove any trapped air.
Start-up and operation
1. Follow the “Start-up checklist,” page 23 to prepare for start-up.
Start-up checklist
Verify that T&P relief valve is properly installed
and piped as directed in this manual and per local
code requirements.
Verify that the DHW tank and boiler-side piping are
complete and are filled with water and pressurized.
Verify that all air has been bled from both domestic
and boiler water systems.
Verify that cold and hot water lines are correctly
connected to domestic water system.
Verify that supply and return piping from boiler is
correctly connected to water heater.
Check all fittings and piping for leaks.
Verify that all wiring is installed correctly.
Set water heater thermostat according to system
requirements. See “Water heater temperature ad-
justment,” page 24.
Start boiler according to the Boiler Manual.
Verify that the boiler and water heater are operating
correctly, per “Water heater temperature adjust-
ment,” page 24.
Review the following sections with the homeowner
or system operator:
•
•
•
Part number GL-E223-ADOC 0614
23
AQUA PLUS indirect-fired water heaters — Product Manual
Hot Water Can Scald!
• Water heated to temperature for clothes washing,
dish washing and other sanitizing needs can scald
and cause permanent injury.
• Children, elderly, and infirm or physically handi-
capped persons are more likely to be permanently
injured by hot water. Never leave them unattended
in bathtub or shower. Never allow small children to
use a hot water tap or draw their own bath.
• If anyone using hot water in the building fits
the above description, or if state laws or local
codes require certain water temperatures at
hot water taps, you must take special precau-
tions:
• Use lowest possible temperature setting.
• Install some type of tempering device, such
as an automatic mixing valve, at hot water
tap or water heater. Automatic mixing valve
must be selected and installed according
to valve manufacturer’s recommendations
and instructions.
• Water passing out of drain valves may be extremely
hot. To avoid injury:
• Make sure all connections are tight.
• Direct water flow away from any person.
Water heater temperature adjustment
General notes
• Household water usage patterns will affect water temperature at
any faucet or shower.
• Occasionally check temperature at each point of use, then
adjust thermostat accordingly.
• Always recheck temperature after adjusting thermostat.
• When hot water is used in repeated small quantities, a “stacking”
effect can develop in hot water tank. The upper layer of water in
tank can be much hotter than lower layers.
• Lowering the thermostat setting or installing automatic mixing
valves as indicated in these instructions will reduce water tempera-
ture levels. Consult your installer or service technician.
At no time should boiler limit control be set above 200°F.
This can cause severe personal injury, death or substantial
property damage if ignored.
Studies have indicated that dangerous bacteria, includ-
ing , can form in the potable
water distribution system if certain minimum water
temperatures are not maintained. Contact your local
health department for more information.
Setting the thermostat
1. The water heater thermostat is factory set to its lowest temperature.
This may or may not be suitable for your needs.
2. Turn thermostat knob
clockwise to increase water tempera-
ture.
3. Turn thermostat knob
counter-clockwise to reduce water
temperature.
4. When decreasing temperature setting, the stored hot water must
be drawn off before checking temperature at faucet.
5. Check water temperature at a hot water faucet immediately after
first heating cycle. Further temperature adjustment may be neces-
sary as water heating system is used. Recheck water temperature
at faucet after adjustment.
6. When adjusting thermostat, be sure boiler limit control is set a
minimum 20°F higher.
Water heater temperature adjustment knob (on
lower front of water heater)
Part number GL-E223-ADOC 0614
24
AQUA PLUS indirect-fired water heaters — Product Manual
Water heater maintenance
Boiler water — read and comply with all requirements under
“Boiler water restrictions,” page 3.
Water from opened drain valves, unions and other connec-
tions may be extremely hot. To avoid severe personal injury,
death or substantial property damage:
• Tightenalldrainhoseconnections.
• Directhotwaterawayfromallpersons.
ATTENTION USER!
by a qualified service technician.
Follow the
below at least
monthly.
Read “Water heater temperature adjustment,” page 24.
Failure to comply with the above can result in severe
personal injury, death or substantial property damage.
MONTHLY maintenance by user
• At least , visually check valves, pipes and fittings for
leaks.
• Check hot water supply at several outlets. Make sure water
temperature is not too hot.
• Call qualified service technician to repair leaks or address
problems.
MONTHLY maintenance by user
• At least MONTHLY, visually check valves, pipes and fittings for leaks.
• Check hot water supply at several outlets. Make sure water temperature
is not too hot.
• Call qualified service technician to repair leaks or address problems.
ANNUAL start-up by qualified service
technician
Obtain an Inspection and service kit (see “Replacement parts,”
page 39) before attempting to perform the annual start-up.
This kit contains items that will usually have to be replaced.
Check water supply temperature at several outlets to ensure
the water temperature is acceptable for intended use and
that all temperature control devices are functioning properly.
Read page 3 and verify that all requirements are met by the
installation.
Perform any procedures required by local codes.
Verify system pressure both on domestic water and
boiler water sides.
Manually operate T&P relief valve at least once
a year (see Figure 21). This will release some hot
water. Move operating lever to open position for
a few seconds and then move it back, allowing it
to snap closed. After T&P relief valve is operated,
if it continues to release water, close cold water
inlet to water heater immediately. Follow draining
instructions, and replace the T&P relief valve. If
T&P relief valve weeps periodically, it may be due
to thermal expansion. Install an expansion tank if
not already installed.
Follow instructions on circulator to oil it, if oil-
lubricated.
Follow instructions in “Inspect anode and water
heater interior,” page 26.
Check valves, pipes and fittings for leaks.
Check function of all controls and valves (see con-
trol manufacturer’s instructions).
Review homeowner’s maintenance responsibilities
T&P valve operation
Before operating the T&P relief
valve, make sure no one is in front of
or around the T&P relief valve dis-
charge piping. Hot discharge water
can cause severe personal injury or
substantial property damage.
Plugging T&P relief valve or dis-
charge piping can cause excessive
pressure in the water heater, result-
ing in severe personal injury, death
or substantial property damage.
Part number GL-E223-ADOC 0614
25
AQUA PLUS indirect-fired water heaters — Product Manual
Water heater maintenance
(continued)
and their frequencies, including any not listed in the following
paragraphs.
Inspection hatch assembly (hatch cover
shown transparent)
Temperature adjustment knob
Inspection plate (handhole)
Factory wires from thermostat to field wiring terminal block
Field wiring terminal block
M8 hex nut
Inspection plate bracket
The purpose of the is to reduce
the damaging effects of aggressive water on the wa-
ter heater. Aggressive water will cause the anode to
erode.
The anode must be inspected at least annually to de-
termine whether a new anode should be installed.
Severe or rapid deterioration of the anode indicates
very aggressive water. If this occurs, have the water
tested to verify whether it is within the limits given
under “Operating restrictions,” page 3.
Failure to inspect the anode regularly and replace if
necessary could result in damage to the water heater,
causing possible severe personal injury, death or
substantial property damage.
Inspect anode and water heater interior
1. Close domestic water isolation valves.
2. Drain the water heater completely and allow it to cool off.
3. Remove the inspection hatch cover (Figure 24, page 39, item 8).
a. The temperature control bulb will have to be pulled out of the
immersion well, located in the inspection plate.
4. After the water heater has drained and cooled, remove the inspec-
tion plate (Figure 22, page 26, item 2).
There will be some water remaining in the bottom of the
water heater. This can be siphoned off or removed with
a wet/dry vacuum.
a. Partially unscrew the M8 hex nut (Figure 22, page 26, item 5)
while holding the bracket (Figure 22, page 26, item 6). DO
NOT completely remove the nut.
b. Hold and turn the bracket 90 degrees, being careful not to drop
the inspection plate inside the tank.
c. Remove the inspection plate.
5. Use a work light or flash light to inspect the interior of the tank.
6. Use a plastic scraper if needed to remove any accumulation on the
coil. DO NOT use abrasives or metallic objects.
7. Remove as much sediment as possible through the inspection
opening.
8. Rinse the bottom and remove remainder with a wet/dry shop
vacuum.
9. Remove the magnesium anode cover and anode (Figure 24, page 39,
items 10 and 1).
10. Inspect the anode and replace if needed with part list in (Fig-
ure 24, page 39). See WARNING above.
11. Replace the inspection plate gasket if necessary. Then
re-install the inspection plate. Align the gasket carefully.
DO NOT over-tighten the bolt. This could damage or
extrude the gasket, or distort the plate.
12. Re-install the access cover hatch and tighten the four M8
Phillips-head screws. Do not over-tighten the screws.
13. Refill the water heater and restore to operation.
14. Verify operation of boiler and water heater.
Drain the water heater if
necessary during shutdown
periods
1. Drain the water heater if it will be shut off and exposed
to freezing temperatures. Freezing water will expand
and may damage water heater.
a. If boiler water contains sufficient antifreeze, then
only the domestic water needs to be drained.
b. If boiler water does not contain sufficient antifreeze,
then the boiler water and the domestic water must
be drained.
Part number GL-E223-ADOC 0614
26
AQUA PLUS indirect-fired water heaters — Product Manual
Troubleshooting
Preparation for troubleshooting
Tools needed
Electrical meter to measure voltage and continuity.
Pressure gauge (such as Watts #276H300 test gauge).
Temperature gauge.
Stopwatch.
Bucket —
1 gallon or larger, with volume markings.
Suggested parts to have on hand.
Tank thermostat (Aquastat) — see Replacement parts for part number.
Inspection and service kit — see Replacement parts for part number.
Information needed before the service call
Know the water heater model number.
Know the boiler manufacturer and model number.
Have the boiler manual and wiring and piping schematics readily available.
Get the latest revisions from www.Weil-McLain.com.
Review all manuals before leaving for the job site.
Troubleshooting procedures
. Always double-check your results.
Skipping or not completing steps can lead to wrong conclusions, repeated callbacks to the
job site and unhappy customers.
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Troubleshooting
(continued)
Insufficient
hot water
Undersized water heater?
Boiler system improperly sized?
Check component parts.
Check boiler operating tempera-
tures.
Check location of flow control
devices.
Check for air in the system.
Clean the boiler water system.
Check tank thermostat setting.
29
Excessive
domestic water
temperature
Reduce stacking
• Lower boiler operating tempera-
ture.
Install a thermostatic mixing valve.
Install a recirculation loop.
32
Boiler relief valve
lifting or weeping
Undersized expansion tank?
Faulty boiler expansion tank?
Faulty boiler relief valve?
Faulty boiler fill valve?
33
Temperature/
pressure relief
valve lifting
or weeping
Undersized or missing domestic
water side expansion tank?
Faulty domestic water side expan-
sion tank?
Faulty T & P relief valve?
High domestic water supply pres-
sure?
Possible water hammering or pres-
sure spikes?
Check boiler operating tempera-
ture.
34
Water on the
floor near the
tank
Check for leaks from sources other
than the water heater.
T & P relief valve lifting and dis-
charging?
Loose piping connections?
35
Top of tank or
insulation wet
Check for leaks from sources other
than the water heater.
Loose piping connections?
35
Water quality
problems
Water smells like “rotten eggs.”
Milky water.
Discolored water from the hot
water faucet.
37
Typical problems and causes and page location for details
Problem Check possible causes Page
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Troubleshooting
(continued)
1 Undersized water heater?
• There are many methods of sizing various applications, i.e. ASHRAE sizing tables or ASPE domestic water
heating design manual.
• Confirm the water demand required for the application.
• Confirm the flow rates of the fixtures.
• For example, was the tank sized for shower heads at 2.0 gpm, while the actual heads are 5.0 gpm?
• Use a bucket and a stopwatch to determine fixture flow rates.
• Evaluate the hot water usage pattern for a day.
• Is the peak demand unusually high for the application?
• Has the demand for domestic hot water changed since the system was installed?
• A bathroom remodeling project with a newly installed whirlpool tub will substantially change the
domestic water demand.
2 Boiler system improperly sized?
• Can the boiler provide the required output to meet the domestic water load? Determine the boiler domestic
water capacity, GPH, by the following:
=
[Temp. rise °F = Required DHW temp. °F – Incoming temp. °F]
[8.33 = Density of water (lbs/gal) x 1 Btu / lb-°F]
• Example — A single family home with a 3.0 GPM shower fixture and a 150,000 Btuh output boiler ca-
pacity.
• The shower demand of 3.0 GPM equals 180 GPH (60 times the GPM).
• Is the boiler capacity enough to deliver this hot water flow at 115°F for an extended period? Determine
the boiler capacity:
=
• The boiler is capable of delivering 277 GPH (or 4.6 GPM) continuously, which is enough for this
application.
• Measure the BTU input to the boiler by clocking the gas meter or finding the oil flow rate based on nozzle
size and pump pressure.
• Does the hot water system need to be wired for domestic priority? For systems in which either the storage or
BTU’s available are marginal it is recommended to wire the domestic water heater in a priority manner.
• Is the boiler piping to the water heater properly sized to allow the required flow rate for maximum BTU
transfer? The temperature differential of the boiler supply and return water should be 20°F to 30°F.
Insufficient hot water
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Troubleshooting
(continued)
• Is the circulator between the boiler and the water heater properly sized to provide enough flow for maxi-
mum BTU transfer? Check the table below:
¾”
3 Check component parts.
• Is the domestic water thermostat functioning properly?
• Check the water heater thermostat (requires an electrical meter).
1. Disconnect the field wiring to the water heater thermostat terminals.
2. Turn the thermostat knob to the highest setting — clockwise — to initiate a call for heat.
3. Check for continuity across the water heater thermostat terminals. On a call for heat, these contacts
should closed.
4. Continue checking for continuity while turning the thermostat knob to the lowest setting — counter
clockwise — to satisfy the call for heat. The contacts should open, breaking the continuity.
5. If any of these steps fail, replace the thermostat.
• Is the thermostat setting too low?
• If the thermostat setting is too low, the boiler may not have the opportunity to deliver the maximum
BTU’s required to completely heat the entire volume of water stored in the tank.
• During a call for heat by the water heater, does the boiler circulator begin pumping, does the zone valve open,
does the boiler fire? Check every component in the system to ensure they are properly functioning.
Insufficient hot water (continued)
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Troubleshooting
(continued)
4 Check boiler operating temperatures.
• If possible, increase the boiler operating temperature to 180°F or 200°F.
• Maintain a minimal temperature in the boiler during non-heating seasons.
• A boiler typically has a higher standby loss than the indirect water heater.
• After a long standby period, the colder boiler may absorb the stored energy within the water heater
during the initial call for heat.
5 Check location of flow control devices.
• Lab tests have shown that during long standby periods the boiler piping can act as a thermal siphon and
draw stored heat from the domestic water.
• Locate flow control devices (zone valve, spring check valves...) or heat trap loops in the boiler piping
close to the water heater.
• Insulate all boiler piping to and from the water heater.
6 Check for air in the system; check water heater air vent.
• An air-bound water heater or boiler will not circulate system water properly, resulting in a lack of heat
transfer.
7 Clean the boiler water system.
• A dirty boiler system can cause deposits to form on the water heater coil. This insulates the coil, reducing
the heat transfer.
• Clean the boiler system per the boiler manufacturer’s instructions.
• Install a strainer in the boiler piping on older installations or for systems likely to carry sediment.
Insufficient hot water (continued)
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Troubleshooting
(continued)
Excessive domestic water temperature
1 Reduce stacking.
• Excessive water temperature is usually the result of stacking within the water heater.
• Stacking is the occurrence of various water temperatures layering within the water heater with the
hottest water in the uppermost layer.
• This layering or stacking effect typically occurs during small draws of hot water (typically less than
25% of the storage capacity) that are long enough to create a call for heat on the thermostat, but are
short enough not to deplete the stored energy within the tank.
• Excessive stacking can occur when frequent short-to-moderate draws are taken in quick succession.
• During this condition, the temperature of the domestic water can approach the temperature of the
boiler water.
• REMEMBER — All water heaters (direct or indirect) will stack.
• To reduce stacking within the tank:
• Reduce the boiler operating temperature to 160°F - 170°F. This will limit the maximum domestic
outlet water temperature during high stacking water usage.
2 Install a thermostatic mixing valve.
• Installing a thermostatic mixing valve will provide uniform delivery temperature with minimal regard
to water usage.
3 Install a recirculation loop.
• Installing a properly-sized recirculation loop not only provide prompt delivery of hot water, but it will
provide circulation and mixing of the water within the tank.
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Troubleshooting
(continued)
Boiler relief valve lifting or weeping
1 Undersized expansion tank?
• Insufficient allowance for expansion on the boiler side can cause the boiler pressure relief valve to lift.
• The additional quantity of boiler water contained in the outer tank must be considered when sizing the
boiler side expansion tank.
2 Faulty boiler expansion tank?
• Is the expansion tank defective, waterlogged or improperly charged?
• Check for failed gaskets or bladders, or a faulty Schraeder valve.
• Use a tire gauge to check the charge pressure of the tank.
• Turn the boiler limit up to a higher setting and let the system run at a higher temperature. This will
simulate maximum expansion in the boiler system.
• If the boiler relief valve lifts and/or there is a significant increase in the boiler system pressure, the
expansion tank is flooded or undersized.
3 Faulty boiler relief valve?
• Is the boiler pressure relief valve functioning properly? Dirt and water deposits can accumulate under
the valve seat.
4 Faulty boiler fill valve?
• Is the valve filling to the correct pressure?
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Troubleshooting
(continued)
Temperature/pressure relief valve lifting or weeping
1 Undersized or missing domestic water side expansion tank?
• Is there a thermal expansion tank installed on the domestic supply piping and is it properly sized?
• A thermal expansion tank is required if the domestic supply piping includes a backflow preventer or pressure reducing
valve.
• Ensure the potable water expansion tank is properly sized according to the water heater volume and supply pressure.
• During long periods when there are no draws from the tank (i.e. overnight), the T&P relief valve may lift or weep due to
thermal expansion, but may function properly during normal periods of tank draws.
2 Faulty domestic water side expansion tank?
• Is the expansion tank defective, water logged or improperly charged?
• Check for failed gaskets or bladders, or a faulty Schraeder valve.
• Use a tire gauge to check the charged pressure of the tank.
3 Faulty T & P relief valve?
• Is the temperature/pressure relief valve functioning properly? Dirt and water deposits can accumulate under the valve seat.
4 High domestic water supply pressure?
• Check the domestic supply pressure entering the water heater.
• If the pressure is over 70 psi it is recommended to install a pressure reducing valve. A thermal expansion tank is required
if a PRV is installed.
• This will prevent any pressure spikes or increases in pressure due to thermal expansion which may cause the T&P valve
to lift or weep.
5 Possible water hammering or pressure spikes?
• Check the domestic system for possible sources of water hammering or pressure spikes.
• Some appliances such as clothes washers and dishwashers utilize fast acting valves which may cause water hammering or
pressure spikes through the domestic water system.
• Install water hammer arrestors as required per the manufacturer’s instructions, or install flexible connectors to isolate the
tank from the domestic system.
6 Check boiler operating temperature.
• If the boiler operating temperature is too high, stacking can occur in the water heater raising the domestic water tem-
perature close to the boiler operating temperature. — Reduce the boiler operating temperature to 180°F. Also follow
page 32 suggestions if the problem persists.
Part number GL-E223-ADOC 0614
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Troubleshooting
(continued)
Water on the floor near the tank
1 Check for leaks from sources other than the water heater.
• Check for possible water seepage through foundation cracks. Did the water appear after a heavy rain?
2 Is the source of water from the T&P relief valve?
• Place a bucket under the discharge piping of the T&P relief valve and monitor it for a day or two. This is
a procedure that can be done by the homeowner.
• If the T&P relief valve is the source, refer to page 34 of this guide.
3 Loose piping connections?
• Check all connections – boiler connections, domestic connections, etc.
• Check all the boiler connections to the water heater.
• A build-up of corrosion is a sure sign of a leak.
• Excessive force or water hammer can damage the welds where the piping connections enter the water
heater tank.
• If water is leaking from around one of the tank connections, a weld may have been broken. Contact
your Weil-McLain supplier to determine how to handle the problem.
Top of tank or insulation wet
1 Check for leaks from sources other than the water heater
• Check for possible overhead pipes leaking onto the tank.
2 Loose piping connections?
• Check all connections – piping connections to the tank and elsewhere if the vicinity.
• Check around valve stems.
• A build-up of corrosion around a joint is a sure sign of a leak.
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Troubleshooting
(continued)
Rapid decay of magnesium anode
1 Anodes last less than two years
The purpose of the is to reduce the damaging effects of aggressive water on
the water heater. Aggressive water will cause the anode to erode.
The anode must be inspected at least annually to determine whether a new anode should be
installed.
Severe or rapid deterioration of the anode indicates very aggressive water. If this occurs, have the
water tested to verify whether it is within the limits given under “Operating restrictions,” page 3.
Failure to inspect the anode regularly and replace if necessary could result in damage to the water
heater, causing possible severe personal injury, death or substantial property damage.
Part number GL-E223-ADOC 0614
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Water quality problems
1 Water smells like “rotten eggs.”
• The most common cause of water to smell like “rotten eggs” is a non-toxic sulfate reducing bacteria.
• The bacteria usually enters into the water system through a break in the supply piping or during
construction/maintenance of the supply piping.
• The bacteria survives in the water system by converting sulfate (SO
4
) in the water to hydrogen sulfide
(H
2
S) gas.
• It is this gas that creates the “rotten egg” smell.
• The presence of hydrogen sulfide can also affect the taste of the water.
• Along with the stench caused by this bacteria, black deposits that typically indicate pipe and/or fitting
corrosion may also appear in the water.
In extremely high concentrations, hydrogen sulfide gas can be toxic. However, the gas is detectable
prior to reaching harmful levels.
• The bacteria will thrive in any water system under the following conditions:
• High levels of sulfur in the water.
• Activated hydrogen in the water from cathodic reactions within the tank.
• Water with little or no dissolved oxygen.
• Storing the domestic water below 130ºF.
• Other causes of smelly water:
• Chlorides of magnesium and calcium gives water a bitter taste.
• Chloride of sodium will produce a salty tasting water.
• Sulfates above 50 ppm in the water gives the water a medicinal taste.
• Carbon dioxide in water with a low pH results in water that is fizzy.
• Iron and tannic waters will produce water with a bad taste and odor.
• Treatment
• The treatment of this situation requires the water system to be shock-chlorinated. Depending on the
severity of the bacteria within the water system, several treatments may be needed.
2 Milky water.
• When water is initially drawn from the faucet it appears to be milky or cloudy, but it becomes clear after
the water is allow to stand for several minutes.
• This is usually an indication that the water contains high levels of soluble gases, such as oxygen, chlo-
rine, carbon dioxide, hydrogen sulfide or others.
• As the water system pressure increases, the amount of gas that water can hold in a solution decreases.
• When air and gases are forced out of the heated water, the problem may be evident in one or both of
the following conditions:
• Gases, in the form of small bubbles, may make the water appear milky from the tap, but clear after
several minutes when those bubbles will separate.
Troubleshooting
(continued)
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
• This is similar to the reaction that occurs as air bubbles form on the walls of a pan shortly before the
water begins to boil.
• The release of dissolved gas can also create air pockets and air locks in the water system piping. This
can cause spurts of air or gases when opening the hot water faucet.
• There is generally no cure for milky water caused by dissolve gases, although it can be reduced with aer-
ated faucets. In some applications the amount of air and gases precipitating out of the water will reduced
in time. It should be noted that these gases are not harmful to the end user.
3 Discolored water from the hot water faucet.
• The water from the hot water faucet appears discolored, either rusty, brown, black or yellow.
• Because the tank is stainless steel, which is resistant to corrosion, the problem is not tank-related.
• The problem is usually a non-toxic iron-reducing bacteria that is commonly found in soil, well water,
water treatment plants and piping systems.
• The bacteria usually thrives in systems in which the soluble iron exceeds 0.2 ppm.
• The bacteria will feed on the soluble iron in the water, producing “rusty-color” water as a by-product
of the feeding process.
• Variables in which the bacteria can thrive:
• Elevated levels of iron and manganese in the water.
• Water with little or no dissolved oxygen.
• Water storage temperatures below 140ºF.
• Items that can potentially increase the presence of the bacteria:
• Water softeners.
• Well water.
• Long periods of no water movement.
• Treatment
• Treatment requires the water system to be shock-chlorinated.
• Depending on the severity of the bacteria within the water system, several treatments may be needed.
• Check the pH and chlorides of the water in the water heater tank and the boiler system.
• The pH must be between 6 and 8.
• Chlorides must be less than 200 ppm.
• Note the pH and chloride readings on the warranty sheet.
• Items that can affect the pH reading:
• Water softeners.
• Water treatment plants.
• Cl ( chlorides) added, especially during the summer.
• Fl ( fluorides) added in treatment in large cities.
• Elevated levels of iron, manganese, and sulfur.
• If the pH is high or low, this has a major effect on the metal tanks, piping and heat transfer surfaces.
Water quality problems (continued)
Troubleshooting
(continued)
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
1
Magnesium anode replacement kit
(includes anode, o-ring, insulating
washer and brass bushing)
35/45/55/85 633-500-014
105 633-500-016
2 Thermostat repair kit
Aqua PLUS
Residential
(35/45/55/85)
633-500-020
Aqua PLUS
Commercial
(105)
633-500-021
3 Top plastic cap replacement kit
35/45/55 633-500-024
85 633-500-025
105 633-500-026
4
Bottom plastic cap replacement kit
(plastic cap and 4 screws)
35/45/55 633-500-030
85 633-500-031
105 633-500-032
5 Leveling leg replacement kit (4) All 633-500-036
6
Temperature & pressure relief valve
kit
35/45/55 633-500-038
85/105 633-500-039
NS
Inspection and service kit (includes
inspection plate and anode seals)
All 633-500-042
7 Inspection plate replacement kit All 633-500-044
8
Inspection hatch cover replacement
kit
All 633-500-046
9 Fitting grommet
¾”
1”
633-500-064
633-500-037
10 Anode cover All 633-500-048
NS Jacket replacement kit
35, Pewter 633-500-049
45, Pewter 633-500-050
55, Pewter 633-500-051
85, Pewter 633-500-052
105, Pewter 633-500-053
NS Mixing valve kit, 1" All 633-500-012
Replacement parts
Water heater replacement parts
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
AHRI ratings
AQUA
First Hour
Rating
Continuous
Draw Rating
Minimum
Heat Output
Rate
Minimum
Heat Source
Flow Rate
Heat Source
Friction Loss
First Draw
Rating
Standby
Loss
The ratings in this table are certified by
AHRI. The conditions under which these
ratings were obtained are listed below.
GPH GPH Btu/hr GPM Feet w.c. GPH
Degrees F
per hour
230.0 203.9 134,477 14.0 5.4 26.1 0.9
These ratings were obtained with a heat
source output rate of 134,477 Btu/hr at a heat
source flow rate of 14 gpm. Other results will
be obtained under different conditions.
263.7 228.2 150,488 14.0 8.8 35.6 0.8
These ratings were obtained with a heat
source output rate of 150,488 Btu/hr at a heat
source flow rate of 14 gpm. Other results will
be obtained under different conditions.
322.9 265.8 175,320 13.9 4.2 57.1 0.5
These ratings were obtained with a heat
source output rate of 175,320 Btu/hr at a heat
source flow rate of 13.9 gpm. Other results will
be obtained under different conditions.
341.4 270.3 178,279 14.0 5.4 71.0 0.5
These ratings were obtained with a heat
source output rate of 178,279 Btu/hr at a heat
source flow rate of 14 gpm. Other results will
be obtained under different conditions.
453.7 373.0 245,926 14.0 7.1 80.8 0.4
These ratings were obtained with a heat
source output rate of 245,926 Btu/hr at a heat
source flow rate of 14 gpm. Other results will
be obtained under different conditions.
®
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Ratings with 200°F boiler supply water
For water heater to achieve the rated performance below: Boiler water must be supplied to the water heater at 200°F,
and the boiler water flow rate must be no less than given in the tables below. (For Ultra Gas boiler, Ultra Oil boiler
or GV90+ boiler applications, with supply water at 190°F, see the ratings in the boiler manual.)
Boiler
Heating
Capacity
MBH
First Hour Rating Capacity (GPH) — Boiler Water Supply at 200°F
DHW
temps
AQUA
PLUS
35
Boiler
Water
Min GPM &
Head Loss
AQUA
PLUS
45
Boiler
Water
Min GPM &
Head Loss
AQUA
PLUS
55
Boiler
Water
Min GPM &
Head Loss
AQUA
PLUS
85
Boiler
Water
Min GPM &
Head Loss
AQUA
PLUS
105
Boiler
Water
Min GPM &
Head Loss
DHW 50°F to 140°F
93
8 GPM
minimum
@
1.6 ft wc
103
8 GPM
minimum
@
1.6 ft wc
124
8 GPM
minimum
@
1.6 ft wc
138
14 GPM
minimum
@
5.4 ft wc
148
14 GPM
minimum
@
7.1 ft wc
120 130 151 165 175
147 157 178 192 202
174 184 205 219 229
201 211 232 246 256
223 237 259 273 283
223 243 286 300 310
223 243 302 327 337
223 243 302 354 363
223 243 302 374 417
223 243 302 374 483
223 243 302 374 483
223 243 302 374 483
223 243 302 374 483
223 243 302 374 483
DHW 50°F to 115°F
119
8 GPM
minimum
@
1.6 ft wc
129
8 GPM
minimum
@
1.6 ft wc
150
8 GPM
minimum
@
1.6 ft wc
164
14 GPM
minimum
@
5.4 ft wc
174
14 GPM
minimum
@
7.1 ft wc
157 166 188 201 211
194 203 225 239 249
231 241 262 276 286
268 278 299 313 323
306 315 337 351 360
337 352 374 388 398
337 363 411 425 435
337 363 443 462 472
337 363 443 537 547
337 363 443 551 640
337 363 443 551 715
337 363 443 551 715
337 363 443 551 715
337 363 443 551 715
Part number GL-E223-ADOC 0614
41
AQUA PLUS indirect-fired water heaters — Product Manual
Ratings with 190°F boiler supply water
For water heater to achieve the rated performance below: Boiler water must be supplied to the water heater at least
190°F, and the boiler water flow rate must be no less than given in the tables below.
Boiler
Heating
Capacity
MBH
First Hour Rating Capacity (GPH) — Boiler Water Supply at 190°F
DHW
temps
AQUA
PLUS
35
Boiler
Water
Min GPM &
Head Loss
AQUA
PLUS
45
Boiler
Water
Min GPM &
Head Loss
AQUA
PLUS
55
Boiler
Water
Min GPM &
Head Loss
AQUA
PLUS
85
Boiler
Water
Min GPM &
Head Loss
AQUA
PLUS
105
Boiler
Water
Min GPM &
Head Loss
DHW 50°F to 140°F
93
8 GPM
minimum
@
1.6 ft wc
103
8 GPM
minimum
@
1.6 ft wc
124
8 GPM
minimum
@
1.6 ft wc
138
14 GPM
minimum
@
5.4 ft wc
148
14 GPM
minimum
@
7.1 ft wc
120 130 151 165 175
147 157 178 192 202
174 184 205 219 229
201 211 232 246 256
202 222 259 273 283
202 222 278 300 310
202 222 278 327 337
202 222 278 343 363
202 222 278 343 417
202 222 278 343 442
202 222 278 343 442
202 222 278 343 442
202 222 278 343 442
202 222 278 343 442
DHW 50°F to 115°F
119
8 GPM
minimum
@
1.6 ft wc
129
8 GPM
minimum
@
1.6 ft wc
150
8 GPM
minimum
@
1.6 ft wc
164
14 GPM
minimum
@
5.4 ft wc
174
14 GPM
minimum
@
7.1 ft wc
157 166 188 201 211
194 203 225 239 249
231 241 262 276 286
268 278 299 313 323
306 315 337 351 360
311 335 374 388 398
311 335 411 425 435
311 335 411 462 472
311 335 411 511 547
311 335 411 511 640
311 335 411 511 662
311 335 411 511 662
311 335 411 511 662
311 335 411 511 662
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Ratings with 180°F boiler supply water
For water heater to achieve the rated performance below: Boiler water must be supplied to the water heater at least
180°F, and the boiler water flow rate must be no less than given in the tables below.
Boiler
Heating
Capacity
MBH
First Hour Rating Capacity (GPH) — Boiler Water Supply at 180°F
DHW
temps
AQUA
PLUS
35
Boiler
Water
Min GPM &
Head Loss
AQUA
PLUS
45
Boiler
Water
Min GPM &
Head Loss
AQUA
PLUS
55
Boiler
Water
Min GPM &
Head Loss
AQUA
PLUS
85
Boiler
Water
Min GPM &
Head Loss
AQUA
PLUS
105
Boiler
Water
Min GPM &
Head Loss
DHW 50°F to 140°F
93
8 GPM
minimum
@
1.6 ft wc
103
8 GPM
minimum
@
1.6 ft wc
124
8 GPM
minimum
@
1.6 ft wc
138
14 GPM
minimum
@
5.4 ft wc
148
14 GPM
minimum
@
7.1 ft wc
120 130 151 165 175
147 157 178 192 202
174 184 205 219 229
181 200 232 246 256
181 200 252 273 283
181 200 252 300 310
181 200 252 310 337
181 200 252 310 363
181 200 252 310 400
181 200 252 310 400
181 200 252 310 400
181 200 252 310 400
181 200 252 310 400
181 200 252 310 400
DHW 50°F to 115°F
119
8 GPM
minimum
@
1.6 ft wc
129
8 GPM
minimum
@
1.6 ft wc
150
8 GPM
minimum
@
1.6 ft wc
164
14 GPM
minimum
@
5.4 ft wc
174
14 GPM
minimum
@
7.1 ft wc
156 166 187 201 211
193 203 224 238 248
231 240 262 275 285
268 277 299 313 322
284 307 336 350 360
284 307 373 387 397
284 307 378 424 434
284 307 378 461 471
284 307 378 470 545
284 307 378 470 608
284 307 378 470 608
284 307 378 470 608
284 307 378 470 608
284 307 378 470 608
Part number GL-E223-ADOC 0614
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AQUA PLUS indirect-fired water heaters — Product Manual
Dimensions
Dimensions and ratings — AQUA PLUS indirect-fired water heaters
(approx.)
DHW
DHW
A B C D E
Gallons Gallons
Inches
NPT
Inches
NPT
Inches Inches Inches Inches Inches Inches Inches Pounds
29.6 1.6
C\v 1 36C\, 7M\, 24 21M\, 7C\, 17B\, 28
94
39.9 1.9
C\v 1 46Z\v 7M\, 26 21M\, 7C\, 21Z\v 37M\,
111
53.1 2.2
C\v 1 60 7M\, 29M\, 21M\, 7C\, 28Z\, 51B\,
122
80.6 2.5
1 1 59Z\x 10C\, 33Z\v 26 8M\, 31Z\x 50C\,
223
109.4 3.5
1 1 59C\v 14Z\v 41C\, 30 9M\, 29B\, 48B\,
238
Boiler water inlet (see table
for size)
Boiler water outlet (see
table for size)
Cold domestic water inlet
(see table for size)
Hot domestic water outlet
(see table for size)
Domestic water
recirculation line (not
used)
Inspection hatch with
thermostat adjustment
knob
Magnesium anode (use
only the anode supplied by
Weil-McLain)
Adjustable leg adjustment
range = 5/8” to 1¼” (add
this amount to the height
dimensions for total height
from floor)
Angle between boiler water
connections and domestic
water connections
Connection for T&P valve
(¾”) — valve supplied
loose with the water
heater; field installed
®
Part number GL-E223-ADOC 0614
44
