Weil-McLain CGA GAS BOILER CGA-5 Series 3 Residential Boilers

User Manual - Page 55

For CGA GAS BOILER CGA-5.

PDF File Manual, 68 pages, Read Online | Download pdf file

CGA GAS BOILER CGA-5 photo
Loading ...
Loading ...
Loading ...
Part Number 550-142-300/0520
55
CGa Series 3 Gas-Fired Water Boiler — Boiler Manual
11b
Troubleshooting — spark-pilot boilers (continued)
CHART 5 –– Spark-ignited pilot –– FLAME light flashing and POWER light on steady
ALSO –– Troubleshooting failure to establish main flame
Electrical shock hazard — Wherever you see
TURN OFF POWER
, follow the instructions. Failure to follow
instructions could result in severe personal injury, death or substantial property damage.
Is pilot flame visible through inspection port ?
No Yes
Are main manual shutoff valve and gas valve open?
No Yes
TURN OFF POWER
to boiler at service switch or breaker.
Open main manual shutoff valve and boiler gas valve (per
Operating instructions in this manual). Wait at least 45
seconds.
Turn on power at service switch or breaker. Allow boiler to cycle.
Does FLAME light flash now?
No Yes
TURN OFF POWER
to boiler at service switch or
breaker.
Remove base access panel
(see Figure 32, item 4,
page 60 for location.
Contact gas supplier to correct
pressure or gas supply.
Check the voltage across
main gas valve terminals
of the gas valve.
Is 24 VAC present there?
Yes No
Make sure ground wire
terminal is securely fastened
to control module mounting
screw.
Verify inlet gas pressure at gas valve:
Natural gas – 5.0” w.c. min/14.0” w.c. max
Propane – 11.0” w.c. min/14.0” w.c. max
Is gas present at gas valve inlet and within above range?
No Yes
TURN OFF POWER
to boiler at service switch or breaker.
Check flame signal – Detach sense lead from ignition control
(Figure 30, Item 8, page 50)
.
Connect negative lead of MICROAMMETER to control sense
terminal
(Figure 30, Item 8, page 50)
. Connect positive
lead of MICROAMMETER to sense wire.
DISCONNECT red wire connected to main gas valve terminal
of the gas valve.
Turn on power to boiler and allow to cycle. As soon as pilot
is burning, the MICROAMMETER should read at least 1.0
microamp.
Is flame signal at least 1.0 microamp ?
No Yes
Check the voltage across
main gas valve terminals
of the gas valve.
Is 24 VAC present there?
No Yes
If the wiring from the
control module to gas valve
is intact, replace the control
module.
Retest.
Verify inlet gas pressure at gas
valve:
Natural gas – 5.0” w.c. min/14.0”
w.c. max
Propane – 11.0” w.c. min/14.0”
w.c. max
Is gas present at gas valve inlet and
within above range?
Yes No
Boiler should be in
normal operating
sequence.
Observe operation
until thermostat is
satisfied and vent
damper has closed.
Verify pilot gas line is not
kinked, obstructed or dam-
aged and is correctly attached
to pilot and gas valve.
Verify pilot ignition electrode,
electrode ceramic and spark
lead wire from control are in
good condition. Spark gap
should be approximately 1/8”.
Correct any above problems,
replacing pilot if burner or wir
-
ing is damaged.
Reinstall base access panel to
operate boiler for retest after
any changes or corrections.
If none of the above corrects
problems, then replace the
control module, reinstall base
access panel, and retest.
TURN OFF POWER
to boiler at service switch or
breaker.
Remove base access panel
(see Figure 32, item 4,
page 60 for location.
Verify pilot burner is securely at-
tached to pilot bracket, bracket
is securely attached to cross-tie,
and there is no corrosion on the
ground path for flame sense.
Verify that pilot flame rod, flame
rod ceramic and lead wire from
control module to flame rod are
in good condition.
Correct any above problems,
replacing pilot if burner or wir-
ing is damaged.
If none of the previous steps
(including replacing pilot)
corrects problem, then replace
the control module, reinstall
base access panel and retest.
If the wiring from the
control module to gas
valve is intact, replace the
control module and retest.
Loading ...
Loading ...
Loading ...