Glad I was not camping

[Bob_Vaughn]

Last night it was 46 at my house and I had the heat pump running in my camper. I checked the temperature this morning and it was 64 degrees inside . Even tho I had the thermostat set at 72 degrees. The compressor just does not run long enough to maintain the set temp and yes it is a ducted Atwood 15000.......I am tired of paying authorized repair centers to fix it and no one has yet to get it to run right.....

[ktmrfs]

Bob Vaughn wrote:

BB_TX wrote:
I would question if the thermostat is accurate. Or very possibly, the thermostat is in a position that heated air flows across the thermostat, warming it before the rest of the air is adequately heated. Possibly redirecting the air flow or moving the thermostat might help.

the compressor does not run long enough to affect the thermostat..
Something is turning off the compressor...

coils may be icing up especially if it is near the dew point. once hey ice up either an electric element comes on to defrost them, or it will wait till the ice melts.

45F is a marginal temp for a heat pump especially if RH is much at all.

home heat pumps will switch over to all resistance heating once it gets cold enough and humid enough to have the efficiency drop to the same as resistance heating or less or if it ices up enough. Usually that's in the 30-40F range.

[Community Alumni]

I figured if it was 46 it would get colder at night if that was the low in the evening

JimR

[pnichols]

Bob Vaughn wrote:

timmac wrote:
I got 2 heat pumps in my motorhome and even with the cold weather we had here a few days ago in Vegas they did not do so well below 40 degrees, if you read the manual about the RV a/c units with heat pumps they are not designed for cold weather fulltime use..

I think I solved my problem. the thermostat is 8 degrees off. So I have to set it at 80 to keep it at around 72 in the camper.....I am running tests now in the cooling mode...

I agree with one of the other posts - you might want to just install a new thermostat for your heat pump.

As an aside, I wonder why there's not higher performance heat pumps available for RV use if one wants to pay for them? A heat pump is the main heat source for our home and it keeps our home in the 70's if we want, during outside temps into the high 20's and low 30's. It's a large capacity high performance one with a variable speed compressor and blower ... so technology-wise, a heat pump can be designed and sized to still maintain good interior living temperatures so as to still delivery the goods in temperatures below 40 degrees outside temperatures.

We keep our RV no lower than 65 degrees when sleeping with electric heaters or it's propane furnace, and in the 70's in the daytime or evenings whenever inside. Our down sleeping bag tent camping days our over.

[memtb]

Crowe wrote:
I would suggest just buying a new thermostat if it's not that expensive. Sounds like it might have a defective sensor.

We keep our house at 62 at night. 64 would be too warm. And it was just below zero at 6 a.m.

And I thought we keep our house cool....64 downstairs. If it’s cold outside, our upstairs runs around 58. Bedroom is upstairs.....good sleeping temps!

[Crowe]

I would suggest just buying a new thermostat if it's not that expensive. Sounds like it might have a defective sensor.

We keep our house at 62 at night. 64 would be too warm. And it was just below zero at 6 a.m.

[Bob_Vaughn]

Now this is weird in the cooling mode the thermostat is right on. but in heat mode (HP) it is 8 degrees off. There must be a reason??

[memtb]

Good Luck Bob.....Sometimes the hardest problem to solve....has the simplest solution! 😉 memtb

[wa8yxm]

Mine was in the 60's as well Very comfortable night's sleep. Oh 35 outside.

[Bob_Vaughn]

timmac wrote:
I got 2 heat pumps in my motorhome and even with the cold weather we had here a few days ago in Vegas they did not do so well below 40 degrees, if you read the manual about the RV a/c units with heat pumps they are not designed for cold weather fulltime use..

I think I solved my problem. the thermostat is 8 degrees off. So I have to set it at 80 to keep it at around 72 in the camper.....I am running tests now in the cooling mode...

[timmac]

I got 2 heat pumps in my motorhome and even with the cold weather we had here a few days ago in Vegas they did not do so well below 40 degrees, if you read the manual about the RV a/c units with heat pumps they are not designed for cold weather fulltime use..

They just don't have enough btu's to keep up, your furnace has more btu's to keep the rv warm during the cold nights..

[memtb]

Bob, I’m certainly not an expert on heat pumps, as while we have them.....we’ve never used them. My limited knowledge consists of a solenoid, downstream of the compressor, which directs ( changes direction of refrigerant flow) the hot discharge to the condenser for cooling ( ac use), or to the inside of the camper. I do know, if the solenoid fails in the ac mode, the outside finned area will get hot ( hot gas is passing through coils to cool)....if failed in the heat pump mode, the outside coils will get cold!

Many compressors ( not sure about) have a low level/volume shutdown to protect the compressor. If your system has said shut-down, perhaps you are low on refrigerant. Most/many/all camper ac units are not designed for a refill of refrigerant! If that is the case, I’ve heard (can’t verify), that some “techs” can install a fill (schrader type) valve in the system for a refill.

I hope that I’m not too far off on my understanding of the ac/heat pump system. Maybe someone can chime in and correct my errors.

[Bob_Vaughn]

JimR 1 wrote:
On a heat pump if the temperature gets lower than 40 degrees or so they will not work and are unable to keep up. My heat pump will shut off after if the temp gets low (outside) or if there is not heat increase at the thermostat after a certain time.

JimR

As I said it wes 46.....the first vent had a temp of 93 then the compressor immediately shut off. The compressor did not run long enough to raise the temp in the camper....

[Community Alumni]

On a heat pump if the temperature gets lower than 40 degrees or so they will not work and are unable to keep up. My heat pump will shut off after if the temp gets low (outside) or if there is not heat increase at the thermostat after a certain time.

JimR

[Bob_Vaughn]

BB_TX wrote:
I would question if the thermostat is accurate. Or very possibly, the thermostat is in a position that heated air flows across the thermostat, warming it before the rest of the air is adequately heated. Possibly redirecting the air flow or moving the thermostat might help.

the compressor does not run long enough to affect the thermostat..
Something is turning off the compressor...