Heating, Air Conditioning, Fridge, HVAC/Electric Furnace
QUESTION: Hello Jim,
I'm helping a friend with a furnace problem.
He has a heat pump outside, and a electric furnace for colder temps when heat pump is off. I've checked elements, limit switches, connections, fan runs but no heat from elements (3). I noticed some water had dripped from the above evaporator over the summer and has rusted a couple of diodes in the circuit board at the bottom. Other than that, I'm stumped! Maybe a relay? how do you test for that?
ANSWER: Hello Dustin, I can better help you if you can get me the Make and model # on the furnace. I have serviced hundreds of electric furnaces so I can give some general info:
The elements will come when the temp in the house is 2* below the thermostat setting, when the heat pump goes into defrost mode, or when the heat pump runs for say 15 minute. If the stat has a emergency switch, have him switch it and see if the elements come on.
Let me know. JIM
---------- FOLLOW-UP ----------
York Model # AHP60D3XH21B
Furnace Model # THGD60S21S1A
Serial # WDK8345759
We tried both settings on the thermostat. No change
Thanks again for your help on this
Hi Dustin, I found the wiring diagram for the furnace. There are 2 sequencers ( relays ) that bring the heating elements on. With the stat calling for electric heat, you need to check the voltage from the stat. There is a terminal strip in the furnace. Put you meter on # 4 and #5 you should have 24v. Then test #4 and #6. This will tell you if the stat is working correctly
Also there are 3 fusible links one for each element. It's not likely all three have opened but it worth checking out.
Let me know what you find. JIM