Home>Discussions>INSULATION & HVAC>Do I need to replace Honeywell T87F 2873 thermostat?
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crepella4
Do I need to replace Honeywell T87F 2873 thermostat?

Thanks for reading. We have what I've read is a good old thermostat. It is a Honeywell T87F 2873 3 model. The problem is the heat will not kick on when it should. The air conditioning works fine, but the heat only works in Fan mode.

I have tried to reset the furnace by cutting the power and waiting 10 seconds. I have also removed the thermostat cover and checked the wiring, all of which looks tight.

Are there any other suggestions I can do, or would you recommend I replace the thermostat?

The back plate to the thermostat is coded 0039 Q539A 1014 3.

The wiring is as follows: (W) white wire (H) red wire (G) green wire (Y) blue wire (B) no wire attached (O) no wire attached.

Our furnace is a 2004 Rheem model # RBHC 17J14SFA. 208/240 volts. I understand our air conditioning comes from a unit on the roof of the condo. Our Rheem model heater does have a humidifier attached to it.

Any advice greatly appreciated. Thank you so much.

JLMCDANIEL
Re: Do I need to replace Honeywell T87F 2873 thermostat?

At the furnace take a jumper wire and jump between the screws where the white and the red thermostat wires are connected. If the furnace runs your problem is either the thermostat or the wiring.

Jack

brewster
Re: Do I need to replace Honeywell T87F 2873 thermostat?

I agree with McDaniel---also try a fine grade piece of emery cloth or sandpaper (or a women's cardboard fingernail file stick) on the contacts of the T-stat---quite often the contacts of the T-stat become encrusted with crud over the years & no longer make contact to energize the furnace on a call for heat.

If you live in a condo, shouldn't you be contacting the condo management to solve this problem??? it would seem to be THEIR responsibility, not yours!

Replacement of the T87 is not recommended, or is it needed.

crepella4
Re: Do I need to replace Honeywell T87F 2873 thermostat?

Thank you so very much for the advice. I will find someone who can do these things for me. The info is so very much appreciated! :) :) :)

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