Heat Pump not heating

[prsmith]

Hi,

I have a 2005 Itasca Suncruiser 35U withe the basement mounted Coleman/RVProducts Model6535-671 Hi-Efficiency 2-tonpacked heat pump (Panasonic compressors)

A/C works Ok but I am not getting heat from the heat pump.

My tech has not dropped the unit yet but he thinks the problem may be a reserving - he subsequently was told by Coleman that they no longer source these valves.

The parts list calls fora 1454A350 heat valve - does anyone have an alternate source or part number?

Would my thermostat be causing the problem?

How can I determine if it is the stat or valve causing the problem?

Thanks for your help

Preston

[Bill in FL]

I had the same problem a couple of years ago. I cycled it a couple of times and it has never happened again. The tech said it was a sticky reversing valve and that they just stick sometimes.

[SuperGewl]

I'm not sure where you are but it may be just too darn cold for the system to work. First heat the coach up on the gas heater, then switch over to the Heat pump and see if it can maintain temperature. The Heat Pump is not designed to work below about 40 degrees or so.

[Ray,IN]

Originally Posted by SuperGewl

I'm not sure where you are but it may be just too darn cold for the system to work. First heat the coach up on the gas heater, then switch over to the Heat pump and see if it can maintain temperature. The Heat Pump is not designed to work below about 40 degrees or so.

10-4 for that! My heat pump will not maintain a comfortable (73-75) temperature in the coach when the outside temperature is below 45*F.

[prsmith]

Thanks for your comments.

Bill - I have recycled numerous times with no luck

Ray and SuperGewl - ambient temperature is not an issue. I am in Mission TX and yesterday it was 85+. I increased the desired temperature to about 5 degrees above ambient, LP furnace kicked in, heat pump blower kicked in, but there was no heat. I recycled about a dozen times and still no heat. AC did do its job when I finished with heat pump test

[skigramp]

Have you tried unplugging your coach from the shore power pedestal for a minute ... and then plugging in again ...

This "reboot" fixed a similar problem for me several years ago ...

[DancinCampers]

If only the indoor blower motor kicks in when in heat mode, I doubt the reversing valves are the culprit. If they did not work, then your system would cool.

The pc board in the basement unit controls all heat pumps functions once the tstat sends the control signal to it.

There is a troubleshooting tree in the manual. The green led on the pc board can give an indication of issue. Also, the high pressure switch could be open.

I am not sure which stage the reversing valves default to, I would check with company. If they default to heat, then they seem to be working, because they would energize to cool.

PM me if you can't find the manuals on RVP's site, I have some from my previous coach.

[prsmith]

Thanks for all of the comments and ideas

First, we really like the heat pump and would buy another rig with it (if I had the money). Because it uses the roof outlets to spew its warm air, all corners of the rig get heated evenly - not like the heat distributed by the LP furnace.

Secondly, I was in touch with Coleman and got a bit of help from them. The tech wanted to know if, when in elec heat mode, my blowers were working (both indoor and outdoor fans were operating), if the compressors were operating (they were) and whether there was voltage between the stat's Blue and white/black wires (the was - 11.9 v). He also admonished me about the low external temperature and room/set temperature issues in two messages . I know all about these concerns and had tried for 4 months to get the elec heat to work using every combination of Set, Room, and ambient external temp you can think of with no joy. Since I responded to his three questions, I was anxious to find out what the next step in the trouble shooting sequence would be. Alas, the next step never arrived because after I checked the requested voltage, the heat pump started to spew heat. All I can think of is that during the measuring process, I nudged a loose wire, set off some kind of current flow that reset something, or invoked the electronic gods. I advised the tech accordingly so I got no more help.

In any case, our external temp in Mission TX is 47F and the heat pump is dutifully keeping us warm..

Thanks again for everyone's input

Preston