Furnace thermostat goes on and off frequently?

Answer 1

I WILL ASSUME THIS IS NOT A POORLY INSULATED LEAKY HOME, IN THAT FREQUENT CYCLING OF EQUIPMENT IN THE AFOREMENTIONED BUILDING WOULD BE NORMAL. 1) CHECK THAT THE CAVITY BEHIND THE THERMOSTAT IS SEALED, WHERE THE WIRING COMES THROUGH THE WALL. (DRAFTS OF THIS KIND CAN CAUSE THIS SYMPTOM) 2) CHECK THE HEAT ANTICIPATOR ADJUSTMENT ON THE THERMOSTAT ITSELF. IT SHOULD CLOSELY MATCH THE CURREND DRAW (IN AMPS) OF THE FURNACE LOADS DURING THE HEATING CYCLE WITH THE BURNER OPERATING. IF YOU HAVE AN AC AMMETER, YOU SIMPLY PUT IT IN SERIES WITH THE "W" WIRE, AT THE FURNACE MAY BE EASIER THAN AT THE T-STAT ITSELF. THE ANTICIPATOR SHOULD BE ADJUSTED TO THE MEASURED METER READING. (BETWEEN 0.2 AND 1.2 AMPS NORMALLY). IF NO METER IS AVAILABLE, SIMPLY INCREASE THE ADJUSTMENT SAY 0.2 AMPS FROM WHERE IT IS SET NOW AND CHECK OPERATION. MANY ARE LABELED "LONGER" WITH AN ARROW POINTING IN THE DIRECTION OF INCREASED AMPERAGE. MANY ELECTRONIC STATS HAVE DIP SWITCHES ALLOWING YOU TO CHANGE THE CPH. (CYCLES PER HOUR) lc