AboutJ Cook Expertise With 25+ years experience, I am familiar with residential, commercial, and industrial HVAC equipment including but not limited to boilers, chillers, reciprocating and screw compressors. I am trained in all manners of control wiring.
Experience I currently have three HVAC licenses and Refrigeration license by the State of North Carolina. I have been in this field for over twenty years. I have been a service technician for a contractor and also worked at a state college in the repair and maintenance of steam lines and equipment. I am currently the Building Maintenance Superintendent for a municipality.
Question My code on my valve ( 2 blinks) indicates that the presure switch is closed and should be open. Is the presure the same as the vacume switch? I checked continuity on the switch and it reads open. I can remove one of the spade connectors and the furnace will start the ignition sequence. I also can turn the on/off switch off on the gas valve and the unit will go ahead and run until it has satisfied the t stat.Can you help? Thanks Mike
Answer You are correct, the pressure or vacuum switch is the same. It is a fail safe switch so in the event of failure, the furnace will not start and it appears it has failed. Turning the switch off and back on resets the safety circuit and in some cases, this one included, the unit may run through a cycle or several, but eventually the part will fail again and cut the unit off. Thanks J
