Heat Pump Issue

[wprantera]

Has anyone had an issue with their rear heat pump? During a Halloween camping weekend weather was chilly but not below freezing, so I decided to just you the rear AC heat pump. My issue is that it was all ice up when I went up to the roof tut o check for debris on the slides. See attached pictures. Do I have a problem?

[CarWin]

Originally Posted by wprantera

Has anyone had an issue with their rear heat pump? During a Halloween camping weekend weather was chilly but not below freezing, so I decided to just you the rear AC heat pump. My issue is that it was all ice up when I went up to the roof tut o check for debris on the slides. See attached pictures. Do I have a problem?

YES you have a problem.............There is NO pictures attached for us to see.

[jimcol]

If your heat pump was iced up there is a problem. I'm confident of that even without a picture.

[wprantera]

How do you post pictures?

[wprantera]

http://www.montanaowners.com/forums/...hp?albumid=161

[wprantera]

I think I did it with a little help. Thank you

[wprantera]

Does anyone have any ideas on how to fix or what's wrong?

[CarWin]

I`m NOT an ac/heatpump mechanic, but anytime Ive had frozen coils like this its either been low freon or excessively dirty coils causing it.

Others may have a better idea.

[jstadler]

There is a sensor under the foam insulation that detects a frozen coil. It may not be positioned properly or is defective. You can talk to the MFG and they will provide you trouble shooting ideas. A frozen coil is a result of the other posts and the sensor. A simple system, I would be concerned if it did not exchange cold air for heat.

John

[TAKPAK]

You may or may not have a problem. The heat pumps/AC systems on these RV's use a small coil, compared to a residential unit. It's basically the same coil they use for strictly cooling units on RV's, but now also use it for extracting heat as well. Because of that, the heat pump doesn't really "heat" very good at anything below 45 degrees outside air temp. Any OSA temp below that, and there just isn't enough "heat" in the air to work well. Getting down around 32 degrees and the coil may very well "freeze up" due to being "overworked" and not enough surface area. I did a test on ours, and pretty much anything below 45 degrees OSA and the pump couldn't really keep up. When OSA dropped to 40 degrees it was a losing battle. Then it's time to bring on the furnace and get the temps back up. Anything above 45 OSA, and the heat pump part works really well.

[Dave Sinclair]

What he said. Anythign below 45 and there is NO heat to extract, so no work and you get freeze up.

[cwestl]

I can see we don't have any AC Guys in the forum. Any heat pump will ice up the outside coil while heating. Same with you home unit if you have a heat pump. Sensors will sense this condition and put it in a defrost mode to melt the ice off the coil. Then it should go back to heating. Of course Home heat pumps will work below 32 Deg. Of course the units on Travel Trailers have a lot smaller coils and are not as good collecting heat from outside air.

[Bkuhn]

Thank you. I brand new, not familar with heat pumps. Its about 37 out now, and heat pump puts out heat, then just runs... no heat, then kicks in heat. I was not sure if ok to leave run. But with your explanation I will not run under 40 or 45
Thank u
You

[CarWin]

TAKPAK, thats good info to have in the memory bank,Thanks for posting it!!

[Daryles]

Lots of good info here. Thanks for sharing your knowledge.
The only thing I can add is sometimes they don't install the AC units correctly and omit placing the freeze sensor on the coils.

[Cat320]

I solved my heat pump issue...I don't use it.