Weil-McLain 550-110-260/0508 Boiler User Manual


 
Part number 550-110-260/0508
52
GOLD CGs Gas-Fired Water Boiler — Boiler Manual
11d Troubleshooting — control module lights (cont.)
CHART 6 PRESS SWITCH light flashing and POWER light on steady
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.
— Usually indicates pressure switch opened during run cycle —
— May also be caused by wind gusts in excess of 31 mph for non-direct vent sidewall-vented boilers —
Boiler should be in
normal operating
sequence.
Observe operation until
thermostat is satisfied
and inducer has
completed its post-
purge cycle.
Remove one of the wires connected to the pressure
switch.
Check continuity across the switch terminals.
Does the ohmmeter indicate the switch is closed?
Inspect and check wire
harness from control
module to pressure switch.
Reseat connector in control
module receptacle.
If harness is intact and
properly seated, but
problem persists, replace
control module.
Retest.
Check air pressure switch per manual Section 11.
Replace if necessary. Retest.
Replace inducer
assembly.
Retest.
No Yes
Remove INDUCER plug (Figure 25, Item 6, page 46)
from plug receptacle of control module.
Place voltmeter leads across the 120 VAC N and
120 VAC H pins of the INDUCER receptacle (left column
center and right column bottom pins).
Does the voltmeter indicate 120 VAC?
No Yes
Are vent or combustion air passages blocked?
No Yes
Clear passages and recycle
boiler.
Recheck boiler operation.
Wait 5 minutes.
Is PRES SWITCH light flashing?
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 blower motor operate?
No Yes
No Yes