Heat pump

[Goliath-goes]

We have a 2020 Montana high country 381th and our heat pump works well down to 40 degrees. My question is the gas furnace is supposed to kick on with heat pump if there’s more than 2 degree difference but it doesn’t do that. Is there a setting I’m missing somewhere? Tia

[travelin texans]

Originally Posted by Goliath-goes

We have a 2020 Montana high country 381th and our heat pump works well down to 40 degrees. My question is the gas furnace is supposed to kick on with heat pump if there’s more than 2 degree difference but it doesn’t do that. Is there a setting I’m missing somewhere? Tia

The differential is 3-5 degrees, mine was nearer 5! It it were only 2 degrees the furnace would most likely be running with the heat pump every time it starts.

[jasin1]

Originally Posted by Goliath-goes

We have a 2020 Montana high country 381th and our heat pump works well down to 40 degrees. My question is the gas furnace is supposed to kick on with heat pump if there’s more than 2 degree difference but it doesn’t do that. Is there a setting I’m missing somewhere? Tia

It may be like the newer digital thermostats I use where it has to lose 2 or 3 degrees..whichever is the differential..in order for the furnace to kick on…Honeywell uses that on their 8000? Series digital tstat set up for dual fuel…you can’t manually raise the temp say 4 deg and make it kick on the furnace like older thermostats..as long as the heat pump is keepin up it will maintain the heat pump setting…now when the temp at night drops drastically it may start losing a degree an hour and the furnace will kick on after the 2 or 3 deg

Don’t know if it uses a outdoor thermister to lock out the heat pump below a certain temp but they also can be set ( on residential) to keep the furnace locked out above certain temps

[sourdough]

From memory; my MHC had the Dometic capacitive touch thermostat. You set it to furnace, heat pump or AC. It did not switch between functions. Around 40 or so the HP became less effective so I either got up at night to switch to furnace or left it on furnace when I went to bed. I changed out to a MicroAir Easy Touch thermostat right away as the Dometics had tons of problems. No issues since.

[ChuckS]

Link to the thermostat I think you have manual...

https://www.dometic.com/externalasse...7112_64643.pdf

If there is an Auto setting for your unit for MODE then yes the furnace should come on if HP cannot meet the demand...

Personally I prefer to run mine with the furnace or the HP selected ONLY and will change modes myself if I know the overnight temp will drop under 40 degrees.

[Goliath-goes]

Thank you all

[dutchmensport]

Mine is exactly like sourdough's experience. Except, I'm still using the original factory installed thermostat. I just know, when the temps reach 45 degrees outside, I have to flip it over to furnace as the heat pump quits blowing warm.