Weil-McLain Standing Pilot Cast Iron Gas Boiler CGA25SPDN User Manual

34

Part Number 550-101-009/0107

 

Follow all procedures given in this manual and light-
ing instructions when operating the boiler. Failure to 
do so could result in severe personal injury, death or 
substantial property damage.

1. 

 After pilot is manually lit, the gas valve provides pilot 

gas and maintains pilot as long as the thermocouple is satisfied. If ther-
mocouple signal drops for any reason, pilot must be manually lighted, 
following the 

damper will remain closed.

2. 

 When thermostat circuit closes, the boiler circulator and 

vent damper are energized. The vent damper drives open. When the 
vent damper is fully open, its end switch energizes the main gas valve. 

4HIS

3. 

 When a limit control opens, the 

main gas valve is de-energized, but circulator con-
tinues to run. When the limit circuit closes again, 
the main gas valve is energized if there is still a call 
for heat.

4. 

 Set heat anticipator 

as shown on wiring diagram, 

.