PENSOTTI PCH 34B H Cleaning Procedure page 27

Combustion Chamber Cleaning Procedure
28. Check for combustion leaks. With the gas still turned off, reconnect electrical power to the boiler. Remove the 4 wire cable from the
combustion blower motor. The fan will now run continually on high speed. Temporarily block the exhaust vent only. Using a soap and water
solution, inspect for leaks throughout the burner assembly and it's connection to the heat exchanger. Verify no leaks are present, then
remove the temporary blockage. Wipe away the soap and water solution with a clean rag. Reconnect the 4 wire cable to the combustion
blower motor.
Check For Leaks
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