Customer had no power for RH on thermostat went to boiler and noticed emergency switch was off going downstairs, flipped switch and turned first floor thermostat on, boiler came on after I had to relight pilot, let run for 5 minutes and pilot went out again, tested thermocouple and found it only putting out 15 MV, replaced thermocouple and tested boiler stayed running, first floor baseboards got hot, second floor pipes got hot, cycled boiler numerous times, pilot stayed lit and waited until boiler cut off at temperature. System operational and working.