Wire Heat pump & Harman accentra 52i to one thermostat

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Feb 15, 2020
Hey everyone,

My wife and I just purchased a Harman accentra 52i for the first floor fireplace of our 2 story home. We have a 2 zone electric heat pump system both units are newer trane units with heat strips. We are located in Pennsylvania. I have been doing some research now for a few weeks about wiring our Harman thermostat wire to our first floor heat pump thermostat. My reasoning behind this, is I would like the pellet stove to be wired to where it can turn on at a certain set outside temperature. When the outside temp hits that set temperature I want the heat pump to shut off, the pellet stove to turn on, and the fan to the heat pump to run. We have a somewhat open concept home and I’d like to circulate the stove heat through the heat pump ductwork. I understand that the pellet stove thermostat does not run on a 24v thermostat. I have been looking into wiring it with a 24v transformer adapter. Has anyone had any luck with a similar concept? I am looking into a WiFi thermostat, possibly a nest so I can incorporate that outside temp without running a sensor. I have seen successful videos of people running their pellet stoves off of a nest but nothing yet utilizing 2 different sources of heat. Thanks in advance!!
What thermostat are you using? What are the specs of your heater pump? Two stage? Electric backup heat? Honestly it’s just easier to put the pellet stove on its own thermostat.

What you are wanting is possible but.. going to take you becoming a thermostat expert with and understanding that will be better than the average hvac technician.

I am familiar with the eco bee and I don’t thinks it’s possible to lock the heat pump out once temps drop below say 35 degrees and have the thermostat run the electric backup heat. So what you will end up doing is setting the pellet stove up as the emergency electric heat using a 24 V relay to isolate the pellet stove from the thermostat 24 V power supply coming from the heat pump. Your heating strips will not be able to be controlled by the thermostat.

Now with this setup the fan would still run I think I’d you set the tstat to control the fan. (I think).

It’s not simple. You might be able to get an ecobe premium to control the hvac fan on the accessory input but it’s sketchy
@EbS-P I have a single stage heat pump with an electric coil. W1,w2,&w3 are jumpered together. I removed the jumper between w1 and w2 on the air handler. Connected w1 from air handler to w2 of nest and w2&w3 (aux heat) from air handler to * (emergency heat) on the nest. I was planning on wiring the stove to w2 aux on nest as well and have a setting that the aux heat (stove) would be used once outside temp dropped below 30°. I have the thermostat wire run to the 24v relay and the wire from the relay run to the stove but I cannot figure out where to tap into on the stove. I have a new Harman accentra 52i with the touch screen. I am almost leaning towards this idea not being compatible with this newer unit.