AC Heat Pumps Problems

[GearyB]

We have a 2011 42QD. I'm having a problem with my heat pumps now that the nights are getting colder. They are functioning intermittantly. They all turn on and blow air. The problem is they don't all blow hot air all the time. At times only two blow hot, the third blows cold. Or vice versa: one blows hot while the others blow cold. The control panel settings are correct. Weird, right? Any ideas of what I should look at to fix the problem?

[SmilingSimon]

Heat pumps for rv or house do not work below 40 degrees, unless you have augmentation that has elec heat elements in line with the ducting somehow.

that is why you also have a propane heater, i assume you do.

you can also use your propane oven for heat - much quieter and no cold air blowing!, but get some fresh air inside daily for safety - propane burning does produce CO and particulates.

or go get 2 or 3 space heaters, move them about to where you are 'living' at the time ??


GL !

[Morich]

Any manual that I have ever read will have a warning of this sort:

Do not use gas cooking appliances for
comfort heating. Can lead to carbon
monoxide poisoning, which can lead to
death or serious injury.

It kills people ever year but there are still those who do it!

[imnprsd]

I would definitely run floor heaters over heat pumps. ...If for nothing else to prolong the life of your ACs that were really designed for cooling.

Us old RV owner use a Suburban heater, which works great. Are you saying your newer RV only has heat pumps installed or cabin heat? ...If so, all I have to say is: "Those cheapskates!"

Note: When you buy a floor heater, the best ones are short-squatty ones... so they do not tip over and break like the tall ones do. I went though one every season until I bought a Vornado brand "cube" looking floor heater that stands about 12" tall and 12" wide, which I still have! Works great!!!

Note: If you run two floor heaters, you need to make sure they are NOT on the same circuit breaker, because 1200W or 1500W each (times 2) will put you over the 15A breaker level.

[jerichorick]

Originally Posted by GearyB

We have a 2011 42QD. I'm having a problem with my heat pumps now that the nights are getting colder. They are functioning intermittantly. They all turn on and blow air. The problem is they don't all blow hot air all the time. At times only two blow hot, the third blows cold. Or vice versa: one blows hot while the others blow cold. The control panel settings are correct. Weird, right? Any ideas of what I should look at to fix the problem?

My 40U is the little sister to your 42QD. You have the advantage of 3 zone HVAC. I have 2 zone with the front 2 units as zone one. With that said, my units do the same thing. The middle unit is the most sensitive to cold and stops producing heat first. I shut the breaker off when this happens.
It is true that the units specs say that 40* is the cutoff for heat. Yet, over the years I have had situations when I was getting heat in temps much lower out of one or more units. I have no explanation as to why. For example, we are in AL parked between 2 houses. We have had a few nights of freezing temps. I have been able to get heat from the units down to 33* according to the thermometer I use.
As to your situation: When a zone goes cold shut it off. Stay with the heating units as long as you can to conserve fuel. I don't recall if your rig uses LP for heating or diesel. Watch the power panel when you start your heat pumps. You should see a 3A increase for the initial unit start and a jump to ~14A per unit when the compressor comes up to speed. If a unit freezes up the compressor will stop and the unit will blow cold air, thus defeating the "working" units.
We live full time in our rig. We have learned to adapt to the many strange ways it behaves from time to time. This is the way of RVing. My simple encouragement to you is to love it for what it is. When the heat pumps stop producing heat switch to gas. Don't be concerned with what the thermometer says.
Happy New Year and many happy trails,
Rick Y

[Joette]

Rv heat pumps don’t often work below 50 degrees because of their size. A home heat pump is much large and can usually work down to 40 degrees.

Besides, with the heat coming from the ceiling, the lower areas will remain cold as heat rises. I prefer using a small ceramic heater on the floor so the coldest areas get the most heat.

[jerichorick]

Originally Posted by Joette

Rv heat pumps don’t often work below 50 degrees because of their size. A home heat pump is much large and can usually work down to 40 degrees.

Besides, with the heat coming from the ceiling, the lower areas will remain cold as heat rises. I prefer using a small ceramic heater on the floor so the coldest areas get the most heat.

RV heat pumps are speced to 40*. Been RVing since '05. My experience is 39* is often the cut off for heat though there are situations, that I just don't understand, that allow the heat pump to work to much lower temps as in my post above. If your heat pump is not working below 50* I suggest you get it serviced. Cleaning the heat exchange fins is a very important maintenance routine. I hose them off at least once a year.



Happy New Year and happy trails.
Rick Y

[Jim_HiTek]

I'm with Rick y, can't really tell exactly when a heat pump thinks it's too cold. My heat pump (basement Coleman unit) worked earlier this season up in the Walla Walla valley down to 28* F. Nearly every night, for several weeks.

Other times, it wouldn't heat unless it was warmer outside. Never able to correlate it to anything.

I'd also recommend a good cleaning of the fins when you can.

[RachelA]

I am confused. Just got a 2000 Adventurer. First use this weekend. Had heat on electric and the first night it worked fine. The second night, it suddenly started blowing freezing cold air from all the ceiling vents. I switched it to gas and it worked fine. My question is why it started blowing the cold air out of the ceiling. Can't find anything in my manual that discusses this

[Jim_HiTek]

How long did you let it run? How cold was it outside?

If it's a basement heat pump, it takes a long time for it to push the cold air from the basement, up the backside of the RV into the house ducting, then all the way to the Living Room. The colder it is outside, the longer it takes. It has never been instantly warm for me, I just put on my long sleeve shirt and run it until I notice I'm getting too warm.

[RachelA]

The temp was in the 40's both nights. The electric heat had been running for two days. We were hooked up to shore power. It was like it just switched to AC. I was able to turn it to gas and problem solved. But, what made it do this. And, I believe my electric heat comes from the floor, not the ceiling. I know my gas heat comes from the floor

Thank you so much for responding and trying to help

[Jim_HiTek]

Yes, gas heat does come from the floor vents. But if you have a 50 amp RV with a TrueAir thermostat, and a Coleman heatpump, than both AC and heat come into the house via the ceiling ducting.

The heatpumps are rated for 40 F or above for heat. Below that, they may not do anything but blow cold air. But that's just a rule-of-thumb, I've had mine function down to 28 F but the air wasn't very warm. But I've also had it not heat when it was up to 50 F. So it depends of many different factors like temp and humidity.

I don't know your specific RV but I believe it's similar to my Journey, and if it has that control panel in the hall between the kitchen and the bathroom, it should show whether or not you're getting the full 50 amps on the 'Service Type' display.

I have a section of my blog that covers the Coleman heatpump and the gas furnace, but I can't answer your questions specifically because I just don't know. I do know one thing though, the 'Shuttle Valve' that switches between AC and Heat on a heat pump in the Colemans are very reliable. Seldom go bad.

Anyway, here's my ad free blog sections covering the basement heatpump. Take a look: Heating & Cooling

Maybe there's something there that will help.

[jerichorick]

Originally Posted by RachelA

The temp was in the 40's both nights. The electric heat had been running for two days. We were hooked up to shore power. It was like it just switched to AC. I was able to turn it to gas and problem solved. But, what made it do this. And, I believe my electric heat comes from the floor, not the ceiling. I know my gas heat comes from the floor

Thank you so much for responding and trying to help

Jim is on the money as usual.
Here is something you could add to your coach for heat: https://smile.amazon.com/Comfort-Glo...s%2C290&sr=8-1
My DW came up with this idea because we had one in the basement she used at one time. We have a fireplace. So with it and the cube we have plenty of heat when it is above 32*. Because we don't want freeze ups in the basement we run gas then.
When running the supplement heat sources, close the ceiling vents to help keep the heat in.
For us getting the LP filled is a problem. No LP stations within a reasonable distance. We are at a residence in Birmingham. We have been using a extend-a-stay with small tanks but, in the cool weather of recent, this is getting expensive, DW saved the banking account some stress when she came up with this idea. We were very comfortable last night with just these devices and the heat pumps shut off.
One last thought. Don't overload the circuit you use for the cube. I tripped a breaker this morning by forgetting this. Coffee pot and cube heater don't play well together.
Happy trails.
Rick Y

[RachelA]

Originally Posted by Jim_HiTek

Yes, gas heat does come from the floor vents. But if you have a 50 amp RV with a TrueAir thermostat, and a Coleman heatpump, than both AC and heat come into the house via the ceiling ducting.

The heatpumps are rated for 40 F or above for heat. Below that, they may not do anything but blow cold air. But that's just a rule-of-thumb, I've had mine function down to 28 F but the air wasn't very warm. But I've also had it not heat when it was up to 50 F. So it depends of many different factors like temp and humidity.

I don't know your specific RV but I believe it's similar to my Journey, and if it has that control panel in the hall between the kitchen and the bathroom, it should show whether or not you're getting the full 50 amps on the 'Service Type' display.

I have a section of my blog that covers the Coleman heatpump and the gas furnace, but I can't answer your questions specifically because I just don't know. I do know one thing though, the 'Shuttle Valve' that switches between AC and Heat on a heat pump in the Colemans are very reliable. Seldom go bad.

Anyway, here's my ad free blog sections covering the basement heatpump. Take a look: Heating & Cooling

Maybe there's something there that will help.

Thank you so much. I understand now. You have been extremely helpful!!!