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Weil McLain HE II Boiler Image 5

The black thing top left of this image is the combustion motor. The round silver disk is the pressure switch. The combustion motor blows toe boiler fumes out of the vent pipe to the outside. The pressure switch detects if the combustion motor is doing it's job. If the combustion motor fails, the pressure switch will not send the OK signal to the control module, and the boiler will not continue. 


Wm II hot water



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