Loading ...
Loading ...
Loading ...
Verify the application will work:
For systems requiring a higher flow than that
recommended in Figure 41 − DO NOT use a direct
connect piping layout. Design system using a
primary/secondary piping layout using guidelines
starting on page 42.
Systems zoning with circulators must use primary/
secondary piping layout using guidelines starting
on page 42.
#HECKSYSTEMmOWRATE
To determine whether direct connection will provide suitable
flow for the intended application, refer to Figure 41.
1. The minimum temperature drop across the heat exchanger
is 20°F. Using flow rates higher than the maximum listed in
Figure 41 is NOT RECOMMENDED.
2. Design zoning to ensure minimum flow rate is maintained
under any call for heat condition that could see full input
rate (High Fire).
Systems using a modulating pump may operate be-
low the minimum flow rates listed in Figure 41 only
if the boiler is operating at a reduced firing rate (low
fire) when doing so. A pump that modulates based
on the system Delta T (ǻT) would provide such op-
eration assurance by varying flow with firing rate.
Use a primary/secondary piping layout if the total flow through
the ECO’s heat exchanger will be higher than the maximum
listed in Figure 41.
#HECKSYSTEMPIPEDESIGN
Only systems with a single system pump zoned with zone valves
may use the direct connect system piping methods shown here.
Any system zoned with zone valves must include a
by-pass pressure regulator. Failure to comply may
reduce pump life.
Expansion Tank Location
Figure 42 and 43 show typical installation of the system expansion
tank. It is highly recommended that you locate the air separator
and expansion tank as shown in the suggested piping drawings
on page 42 and page 43.
Ensure that the expansion tank size will handle boiler and system
water volume and temperature. See tank manufacturer’s instruc-
tions and ratings for details. Additional tanks may be added to
the system if needed to handle the expansion. These tanks may
be installed by connecting to tees in the system piping.
Undersized expansion tanks cause system water to
be lost from the relief valve and makeup water to be
added through the fill valve. Eventual boiler failure
can result due to excessive make-up water addition.
Always locate the cold-water fill connection at the
expansion tank. Never locate this elsewhere.
Diaphragm- or bladder-type tank:
Refer to Figure 42 for suggested piping when using a diaphragm-
or bladder-type expansion tank.
Install an automatic air vent on top of the air separator, per
separator manufacturer’s instructions.
Diaphragm- or bladder-type expansion tank—
Control fill pressure with the tank air charge
pressure. Always check pressure and charge tank
with tank removed from system to be sure reading
is accurate. Boiler relief valve is set for 30 PSIG.
Operating pressure of system, after temperature
expansion above cold fill pressure, should not
exceed 24 PSIG to avoid weeping of relief valve.
&IGURE Maximum and minimum flow rates through
boiler heat exchanger
ECO
Model
MAXIMUM
flow rate
through
boiler
MINIMUM
flow rate
through
boiler
70
6.5 GPM 3.0 GPM
110
10.0 GPM 5.0 GPM
155
14.5 GPM 7.0 GPM
&IGURE Piping to diaphragm (or bladder) type
expansion tank
Direct Connect System Piping
Part number 550-142-122/0513
37
TM
GAS-FIRED WATER BOILER — Boiler Manual
Loading ...
Loading ...
Loading ...