ADC T3000 Tstat with Heat Pump AUX heat running too much

I have an ADC t3000 thermostat installed with my water furnace geothermal two-stage heat pump with LP backup auxiliary furnace.

All seems to be working as it should, however I noticed that my LP furnace is running far too often and I’m wondering if you can assist me with any particular settings that would adjust this.
I am a surety customer and I believe you can see my advanced settings on the thermostat, which I have tried to increase pump staging delay but I continue to notice my propane firing instead of the Geo running to heat my home.

My Geo is on green power and it is far more cost-effective for me to run this for hours, as is designed, then to kick it over to my auxiliary heat source.

Considering the cost of propane I am ready to reprogram the thermostat to tell it I do not have a backup heat source until the time comes that I lose power just to stop burning through the gallons of LP I have so far.

As always, thanks so much for your time, consideration, and any input or assistance you can provide.


Do you notice the temperature dropping a couple degrees below the set point often? In this case it may take a little longer for the Geo pump to keep up with the temperature drop.

One thing to try in this case to keep the aux stage from triggering as often is to adjust the heating differential setting on the advanced page. Try increasing that differential so that the temperature must drop further before the aux stage kicks in.

Hi Jason thanks for the reply.

No I do not see the temp drop that often, but I did have my away degree setting about 3° off of my home setting.

My differential was set at 3° and then I change to 5° yet the furnace still seemed to kick on with LP.

Ideally my LP furnace should be used solely as an emergency heat source as my Geo is sized appropriately for my home and other than needing to run a bit longer, should not require AuX heat for a supplement. This is especially true right now as we are nowhere near the coldest days for my area which the heat pump is sized for.
I have since removed the secondary heat system from my thermostat to remove any chance of firing the LP.

My fear here would be of course if we lost power and I happen to be away, my LP furnace would not turn on to keep the house heated which could be disastrous in the winter. Otherwise I do not anticipate being away for any extended time.

I suppose I could reconfigure the thermostat when needed, for being away an extended period of time…not ideal either.

Can you confirm this is how the various settings work?:
I thought the temperature differential was also what was used to engage the next stage of my heat pump along with the pump timing delay?

Which one takes precedence?

I do not want my heat pump to run in the first stage for longer than it needs if it could satisfy the heating call within the second stage.
What I do not want to have happen is the pump delay time run out on my heat pump second stage which I believe would then kick off the aux LP heat stage, correct?

If I set the aux stage delay timer to a high setting does this delay the LP from coming on for that many minutes after the second stage heat pump has been running or does that require the LP to run for however many minutes I set on that delay until it shuts off?

I thought the temperature differential was also what was used to engage the next stage of my heat pump along with the pump timing delay?
Which one takes precedence?

It’s my understanding that these two settings work in tandem and the first criteria met activates the next stage.

In general setting a longer timer or higher differential should increase the time before additional stages run, including the aux.

I’m happy to reach out and see if I can get extra clarification from ADC.

I think so that we can best assist and describe the issue to ADC, we will need to provide them with data on the frequency the aux is running.

Set your delay and differential and then test over a period of time. Note how long it takes after a call for heat before the Aux furnace kicks in, and note the temperature when this happens.

Some examples of when the aux is running should help identify what is going on.