51
Part Number
550-110-290/0219
CGt
GAS-FIRED WATER BOILER — Series 2 —
Boiler Manual
Troubleshooting — control module lights
(cont.)
12c
CHART 3 –– PRESS SWITCH
& POWER light flashing
–– Usually indicates pressure switch stuck closed or failed to make within 5 minutes ––
120
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.
• Reset boiler control by turning off power at service switch or turning down thermostat for at least 45 seconds.
• Thermostat should call for heat and appropriate zone valves open.
Does inducer motor operate?
No
Yes
• Replace control module.
• Retest.
• Check air pressure switch
per manual Section 12b,
page 46.
• Replace if necessary.
• Retest.
• Clear passages and recycle boiler.
• Recheck boiler operation.
• Try reseating plug in
module receptacle and
restart.
• If inducer still does not
work, replace inducer
assembly.
• Retest.
• Boiler should be in
normal operating
sequence.
• Observe operation until
thermostat is satisfied
and inducer has
completed its post-purge
cycle.
• Remove
INDUCER
plug (Figure 33
, Item 6
, page 48) from
plug receptacle of control module.
• Place voltmeter leads across the
120VAC N
and
120VAC
H
pins of the
INDUCER
receptacle (left column center and
right column bottom pins).
Does the voltmeter indicate 120VAC?
No
Yes
• Remove one of the wires connected to the pressure
switch.
• Check continuity across the switch terminals.
Does the ohmmeter indicate the switch is closed?
No
Yes
• Wait 5 minutes.
Is
PRESS SWITCH
light flashing?
No
Yes
• Wait 45 seconds.
Does Inducer motor operate?
No
Yes
Are vent or combustion air
passages blocked?
No
Yes
