Time to replace the AC/Heat Pump units ?

[piper guy]

Hi all !

Hope everyone had a good Christmas and is continuing to enjoy the holiday season.

Our coach is now a little more than 7 years old and we have been full time for the last 3 years. Consequently our AC units get used a whole bunch more than the usual RV. Today, the rear unit, which is also a heat pump, started blowing just lukewarm air when on heat. Before it has done well. In the little I know about HVAC, I’m thinking that I’ve got a leak in the refrigerant in the unit and it is getting ready to go visit it’s ancestors. If there is something I should check before condemning it, please let me know.

I’m thinking that instead of trying to fix it, it might be time to replace them both. The front unit is AC only and a year ago I replaced the fan motor and now it’s vibrating again.

Back when ours was built, it was an option to add a heat pump to the front AC. Had I ordered ours, I would have. Dealer was too cheap to add $400 which is what the option was back then.

Units are Coleman Mach RV. 15,000 btu each.

Has anyone replaced theirs ? If so, did you add a heat pump to the front one? And how much of a pita was it to run the new wiring harness from the thermostat ?

I’m thinking the new units are much more efficient. My neighbor has a new Keystone with Dometics and can get reliable heat out of them even down under 30 degrees outside temp. Best mine ever did, even when new, was down to about 38.

Ideas and suggestions are welcome and encouraged !!!

Thanks in advance

[RomanyLife]

Hi Piper Guy! Well, I've been away from this forum a long time, and it's time I came back. We are, after all, going to be at the rally!

We have replaced the rear heat pump/AC on ours for the same problem. I am not sure what the actual problem with yours is, but after spending some $$$ on having it diagnosed, it was the internal switch that changes from heat to cold that went bad. A very common problem, apparently. It essentially cannot be repaired. We replaced the unit (had it done at the service center) with a low-profile unit. All told, it cost about $1200 to have done, and I would NOT attempt to haul that heavy thing and try to do it, but that's up to you.

ALSO: and this is important. When I ordered this RV from the factory, I thought, well, one heat pump is good, TWO must be better. Cannot disagree more now. We have ***NEVER*** needed to run BOTH heat pumps. One is enough. Remember, as you mentioned, temps below about 35 render them ineffective anyway. One has always been enough, and I have nearly 6 years of use to back me up on that. I would never have two again. I would only replace your rear hp unit, and call it a day!

When the forward unit gives up, I will probably replace it with another dual model simply because the wiring is already done and the cost difference isn't that significant. So far, so good, though, knock on wood.

NOW, I will see you on another thread, because I have a question for you! Haha! Theresa (Geez, I better get some updating on our signature block done, good grief!!)

[xtasee]

Vaughn, you may also check the wiring harness to the t-stat. I can not imagine that they actually build a different harness with two less wires. I would rather suspect that the wires are there and not used. However stranger things happen.

[piper guy]

Good point Larry.

Theresa, good to hear from you !! Do you happen to have the model number for the one you replaced it with ? And are you happy with it ?

[RomanyLife]

Hi V! Yes, we are happy with it, tho I will say that it is slightly louder than the original. Those are pretty quiet. We love the low profile tho. It's the Coleman Mach VIII 15K BTU, model I believe is: 47204B879. We also installed an easy start on both units when we upgraded our system with solar. Made a big difference.

[XCMARK]

You may want to pull the top plastic cover off and wash out the roof coil , If they get plugged up with dust and crap your heat pump will not perform as well as expected. They sell a acid washer for HVAC coil washing . Just turn off the power and get in be back side of the outside fan and wash it with a mildly strong stream , not to hard your done want to bend the aluminum fins. Best of luck , hope this helps

[ted 95]

We have 2 - 1500 heat pumps and when we just had them both replaced under warranty my dealer first argued they could not both be heat pumps. I always use the 2 units. This year we just went through 15 days of rain and cold here in florida
Was really glad to have both. The air comes out HOT not just warm. And to night and tomorrow it is supposed o be 50ish. Nope get 2....if u can...

[mhs4771]

When we ordered our '16 39MB we added the Heat Pump option to both ACs