Heat.

[Mollysdad]

The other day someone posted about the gas heat coming on automatically below freezing.
Everyone posted that it's controlled by the thermostat, and so it must be turned on, like the A/C or HP or fan. I agreed.
But I recalled that Monday morning when I arose to discover it was 26f outside, I had been running the heat pump roof AC all night. But as I walked up front, I distinctly remember feeling warm air on the floor. Usually the HP makes the warm air hug the ceiling because it uses the ducts. I wondered if there is a fail safe for the gas heat to provide some warm air to prevent the plumbing and tanks freezing? Without human intervention.

Was I dreaming? That was the only day I felt it and the only day the temp fell below 32f.

[Bigventure]

That’s a good thing. I though the thermostat had to be in auto for it to change sources.

[Protagonist]

Originally Posted by Mollysdad

I wondered if there is a fail safe for the gas heat to provide some warm air to prevent the plumbing and tanks freezing? Without human intervention.

Was I dreaming? That was the only day I felt it and the only day the temp fell below 32f.

If that's something unique to newer models, it's news to me. I suggest further experimentation to verify your hypothesis.

[overlander63]

Unless there is a malfunction or a dip switch thrown incorrectly somewhere, the furnace is not supposed to initialize unless either furnace or auto is selected. It should not spontaneously begin working all by itself.

[dznf0g]

On my ccc1, if I select heat pump and auto fan, it will switch to furnace automatically....assuming that one resets the t-stat after having 12v shut off (store switch, for example)

[uncle_bob]

Hi

If it's 26F outside, the heat pump has long since shut down. It's going to get pretty cool pretty fast under those conditions. Most of them get ineffective in the low 40's and shut off totally in the 30's. As with anything on an RV, there is no way to ever say "always".

Bob

[Mollysdad]

Originally Posted by dznf0g

On my ccc1, if I select heat pump and auto fan, it will switch to furnace automatically....assuming that one resets the t-stat after having 12v shut off (store switch, for example)

I did have HP and auto fan.
Very interesting!

The furnace blower must be pretty quiet, then, I remember my old gas furnaces sounding like a jet engine.

What's a ccc1?

[dznf0g]

Originally Posted by Mollysdad

I did have HP and auto fan.
Very interesting!

The furnace blower must be pretty quiet, then, I remember my old gas furnaces sounding like a jet engine.

What's a ccc1?

First generation ccc. Used up to about 2010ish?? Reset to make hp and furnace work together is to shut off t-stat with switch on bottom; press and hold top and bottom buttons while turning on bottom switch. "FF" will appear on screen with successful reset. This must be done anytime 12v is removed from t-stat.

[Tsunami-v2]

Very interested in learning how to setup T-stat to have the heat pump run and then to automatically switch over to propane furnace when it's too cold for the heat pump. Anyone have this knowledge or expertise?

[aftermath]

Originally Posted by dznf0g

First generation ccc. Used up to about 2010ish?? Reset to make hp and furnace work together is to shut off t-stat with switch on bottom; press and hold top and bottom buttons while turning on bottom switch. "FF" will appear on screen with successful reset. This must be done anytime 12v is removed from t-stat.

Uh, what? I have had my trailer for 8 years and have never reset the thermostat. I remove the batteries each fall and replace them in the spring. Furnace and AC function perfectly without the reset. I am not sure what you mean by your statement above.

Actually now that I think of it, I did reset it once. Had trouble with AC coming on but that didn't happen until well into the camping season. The reset sequence you mentioned is nice to know.

[dznf0g]

I helped my bro-in-law do it with his ccc2 once, but we needed the manual and his dealer on the phone to get it done. I just don't remember now, sorry.

[dznf0g]

Unless you reset, the auto switch over to furnace at 37*ish will not happen. Everything else will work fine. Aftermath, do you have ccc1 or ccc2? My comment only concerns ccc1.

[Mollysdad]

I have this. Maybe I should consult the manual. I see button "program" which I've never used.

[overlander63]

Originally Posted by Mollysdad

I have this. Maybe I should consult the manual. I see button "program" which I've never used.

"Prog1" means you have something programmed into it. If you programmed a furnace setting and temp into it, it will come on for the duration and temperature you programmed into it.

[Mollysdad]

Dometic makes downloading manuals torture. I found it elsewhere.

I found this quote

“AUTO” - Auto Change Over Mode
In the AUTO mode the system will automatically change the mode of operation from cool to heat or from heat to cool. In order for this mode to operate, the zone being programmed must contain either a heat pump, heat strip or furnace heating source. When in the AUTO mode, all pre programmed operations for the heat pump, heat strip, and furnace will apply.
Auto Change Over Cooling: If the room temperature rises above the temperature set-point by 2 degrees, the air conditioner will turn ON until the room temperature reaches the temperature set-point at which time the air conditioner will cycle off. Auto Change Over Heating: If the room temperature goes below the temperature set-point by 2 degrees, the available heat source will be cycled ON until the room temperature reaches the temperature set point at which time it will cycle OFF.
If more than one heat source is available on this zone, the priority for selecting the heat source will be heat pump (first), furnace (second), and heat strip (third).


However, I was not in Auto mode, I was in HP with the fan on auto. (The image above is from Google)
I'm not aware of a program, unless the dealer did it.

[overlander63]

Originally Posted by Mollysdad

I'm not aware of a program, unless the dealer did it.

"prog1" IS something programmed into it. No matter who did it, it has been done. If there wasn't anything, it wouldn't show up.

[OTRA15]

Originally Posted by Mollysdad

. .
Maybe I should consult the manual.
. . .

Bingo!

Also suggest doing a hard reboot, per the Dometic manual, to reset the thing to factory default settings, thus getting a clean slate and eliminating any programmed settings.

"Dometic stat hard reboot" -- https://www.google.com/search?ei=cQn....0.vhv8IV0Nd3c

Good luck!

Peter

[AlanMcD]

I just read the Airstream Winter Camping Guide for the heck of it, the one they sent probably all of us, and it had a short blurb saying that the heat pump works down to 30 degrees then the furnace kicks on automatically. It was on page 16, item #2 of the guide and the quote is:

Note: The heat pump will not operate below 30 degrees Fahrenheit, and will automatically switch to the furnace below that temperature

-Alan

[Protagonist]

Originally Posted by AlanMcD

I just read the Airstream Winter Camping Guide for the heck of it, the one they sent probably all of us

Never even heard of the Airstream Winter Camping Guide until now.

But since my Airstream doesn't have a heat pump, I don't guess it matters in my case.

[Tsunami-v2]

My wife said she read the Airstream Winter Camping Guide. I asked her to give me the "Cliff Note synopsis" and she said the guide basically recommend going to Florida for the winter!