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Monkeyman_and_L's avatar
Monkeyman_and_L
Explorer
Nov 11, 2017

Too smart a thermostat?

Freeze warning in our area tonight, and they ain't kidding. Hadn't dumped fresh tank and needed to purge lines. So much easier on the class A.

Then I decide to keep coach warm so I can follow up tomorrow with final winterizing stuff. Air purge and pink stuff into drains and tanks.

Set thermostat for both zones to 60, dial to heat pump. Notice the furnace kicked on. Hmmm, not what I wanted, so I remove the furnace fuse.

Come out later to do a couple more quick items, notice coach interior at 37 degrees, both zones. Started troubleshooting. Notice that after I reset the power on the thermostat and set up temperature demand, the unit flashed between heat pump and furnace.

Reinstalled furnace fuse, opened propane tank, cycled twice because of air in the line and timeout. Furnace now heating.

So, is it just smart enough to know it can't jump the temp 23 degrees to insist on the furnace being active?

This heating system has me baffled. Gotta sort it out.

Anyone else?
Class A

26 Replies

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  • Monkeyman_and_L's avatar
    Monkeyman_and_L
    Explorer
    Nov 11, 2017
    Checked this morning before going to work. Unit is at expected temperature. 1/6 of my propane to do it.

    I have a heat pump at home. I did my research on that one, and it's effective to about 20 degrees outside before activating emergency heating.

    I know that the Duo-Therm units on my coach are what's offered, and I can't easily spec ones that work in a wider temperature range. I also know that due to the size of the units that the performance will not be as high as my home heat pump. Just figured it would take a bit longer to hit the requested temps.

    Mind you, if I had natural gas service at home, I'd make that the emergency heat source in a heartbeat. When it gets sub zero, I could make heat off the friction from my electric meter.
  • 3oaks's avatar
    3oaks
    Explorer
    Nov 11, 2017
    Bumpyroad wrote:
    and they all suck IMHO. I've had a bunch of them and when they are putting out 85 degree air, it feels and is cool on the skin. only time they are comfy is when the electric coils kick on.
    oh to be on a natural gas line again.
    bumpy
    Putting out 85 degree air and feels cool on the skin? Sounds like you need a humidifier. :?
  • 3oaks's avatar
    3oaks
    Explorer
    Nov 11, 2017
    YC 1 wrote:
    Yes these things are very smart.

    Some heat pumps don't work below 40. Some go a bit further.
    That's it, plain and simple. Not much more for the O.P. to figure out. Appears the heating system is operating like it should.
  • Bumpyroad's avatar
    Bumpyroad
    Explorer
    Nov 11, 2017
    YC 1 wrote:
    Yes these things are very smart.

    Some heat pumps don't work below 40. Some go a bit further.


    and they all suck IMHO. I've had a bunch of them and when they are putting out 85 degree air, it feels and is cool on the skin. only time they are comfy is when the electric coils kick on.
    oh to be on a natural gas line again.
    bumpy
  • YC_1's avatar
    YC_1
    Nomad
    Nov 11, 2017
    Yes these things are very smart.

    Some heat pumps don't work below 40. Some go a bit further.
  • Mandalay_Parr's avatar
    Mandalay_Parr
    Explorer
    Nov 11, 2017
    Heat pumps don't work below freezing so they automatically turn furnace on.
    Propane is best way to keep everything warm.

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