Basement AC gone...

[Jim_HiTek]

Coleman 6535-671 basement air heat pump.

Recently the AC went out, and from testing I found there wasn't any air out of the outside fan. Crawled under the RV and spun the squirrel cage fan which is obviously bound up. Does not spin freely.

So I may have a bad motor or bad capacitor but won't know until next week when I pull it out from it's compartment.

My question is, does a non spinning outside fan cause there to be no cooling? Even at start up? The inside fan is working fine. Wouldn't I feel cool air until the condenser froze up?

Just want to be ready to test different things if necessary while it's out of the compartment.

[Tachdriver]

Sounds like the bearing of the fan. Wonder if you could remove it and match it up with a commercial supplier or Coleman. If you can replace it, it won't necessarily be a bad thing to replace your capacitor. It does not sound like it's bad but doing a bit of maintenance now means longer running before next breakdown of same component.

[RichardE]

Non spinning outside fan, otherwise known as the condenser fan, will not aid in the condensing of the high pressure vaporized refrigerant into high pressure liquid refrigerant. Pushing vapor through the expansion valve is not the same as pushing liquid through the valve in terms of cooling.

In a short period, the high pressure will cause so much effort on the compressor that the thermal overload will shut the compressor down.

So, replace the motor, and while you have the unit out, rig temporary power and run the unit to see if the condenser motor was the only issue.

I would replace the capacitors while I had easy access.

[Jim_HiTek]

Hmm. That sounds like there should be some cooling for a short while. I'll have to check that when I pull it out of the compartment. Waiting for cool weather that starts tomorrow. And I'll try to free up the fan motor first. I changed the caps back in '19 but they can go bad early though not likely. The symptom of 'hard to turn' probably means a bushing went out but the squirrel cage isn't loose and doesn't make noise when I turn it. So I'm hoping that the bushing oil gave out and they need some good oil.

Then if I get it to turn easily for a few minutes, I can check for cooling and follow the troubleshooting chart to verify if it's a compressor or something else.

Thanks for the advice.

[Ray,IN]

Originally Posted by Jim_HiTek

Hmm. That sounds like there should be some cooling for a short while. I'll have to check that when I pull it out of the compartment. Waiting for cool weather that starts tomorrow. And I'll try to free up the fan motor first. I changed the caps back in '19 but they can go bad early though not likely. The symptom of 'hard to turn' probably means a bushing went out but the squirrel cage isn't loose and doesn't make noise when I turn it. So I'm hoping that the bushing oil gave out and they need some good oil.

Then if I get it to turn easily for a few minutes, I can check for cooling and follow the troubleshooting chart to verify if it's a compressor or something else.

Thanks for the advice.

If the fan motor is good, and shaft bushing froze, the motor will be humming and eventually trip a breaker, or let the smoke out.
If you pull it out per Duner's instructions, replace the shaft bushings with bearings, (pillow blocks)
There is no need to disconnect incoming 120VAC when pulling the unit, again per Duner's insructions.

[Jim_HiTek]

Dunner's instructions! What about mine! Snort.

I'm set up with a platform and it's cool tomorrow so I'll try to get it out tomorrow.

[hypoxia]

On a stick house if the condenser fan does not spin the compressor will overheat and trip in just a few seconds. There will be no cooling at all.

[Jim_HiTek]

Well, the motor not only has bad bearings (bushings unfortunately) but also has compromised windings. One or two of the coils have obvious melted wires. So the motor is trash. Had run far too long and got old and tired.

So, checking with a motor repair shop, where it turns out I worked at back in the '70's one summer while in college getting my electronics degree, they pointed out that it's a goner, better as a boat anchor then a motor and that they couldn't get a new or used or sub replacement as the 875 RPM 2-speed was weird/odd/custom/ and basically unavailable at a better price then the $500 I was finding. (Could I rewind the windings and put in new bushings since I learned how while working at that motor shop decades ago? Probably, but it wouldn't be easy).

Checking google, I find that a new motor is $500. And so I'm trying to find a mobile HVAC tech that would be able to tell me if the compressors are okay or not. Changing the motor would be the least expensive course of action, but it would be non-returnable if I installed it only to find the compressor(s) was/were bad. AND the compressors may have been badly stressed when the condenser motor burned out and didn't trip the breaker fast enough. The last time the compressors ran the air was very cold, just like a new AC but...the heat pump is 22 years old, and even though I pulled a maintenance procedure on it in 2019, how many years more can those compressors function?

So, this long holiday weekend I've been thinking about it and what I'll do is buy a used 8K to 10K window AC and put it in my RV's LR as a temp solution. Then, I'll try to decide whether or not to modify my basement to install two mini-split units in that space and integrate them to the IN/OUT venting setup that is already there for ~$2,000. Probably take me 50-70 hours of engineering and grunt work to get it installed and working. Not sure I'm up to it any more. I really like the ceiling ducting and would hate to abandon it.

OR, I could just buy a new Coleman Mach unit for $4000 and install it in 1 hour.

Big problem is the weather. It's already in the 80's here and I don't have much time to make a decision and get the work done. Buying a new Coleman seems to be the easiest option at this point (installing the wiring from old to new is not hard for me). Maybe not the best or cheapest though. I suspect a 8,000 BTU window unit I'm planning on buying does the job and works fine for me for a month or two. Once I buy and install it that is. That could give me lots of time to work on the mods to the basement but only early AM and late evenings when it's cool. Or to finally decide to just get another Coleman.

Decisions decisions. Anyway, thanks for the comments.

[chuckftboy]

The 8,000 btu window air is 1/3rd of the basement air you have now. If you are having a rough time with the heat now, July and August will be unbearable with only 8,000 btu's of cooling

[Jim_HiTek]

Originally Posted by chuckftboy

The 8,000 btu window air is 1/3rd of the basement air you have now. If you are having a rough time with the heat now, July and August will be unbearable with only 8,000 btu's of cooling

I am aware. Just a temporary AC unit while it's still half way balmy here. The Coleman is 26,000 BTU after all.

[l1v3fr33ord1]

Jim-

I suspect you ran across this in your career, but for those who may not have...

When a customer of mine asked for solutions to a problem, I'd focus their thinking by saying this:

We can make it good.
We can make it cheap.
We can deliver it fast.
Pick two.

Four thousand dollars, an hour's work and then it works like new? I know which two I'd pick.

[Jim_HiTek]

Originally Posted by l1v3fr33ord1

Jim-

I suspect you ran across this in your career, but for those who may not have...

When a customer of mine asked for solutions to a problem, I'd focus their thinking by saying this:

We can make it good.
We can make it cheap.
We can deliver it fast.
Pick two.

Four thousand dollars, an hour's work and then it works like new? I know which two I'd pick.

But you lose the thrill of the innovation, design, and construction cycle by going the easiest route...That's my favorite part.

And I have to consider, based on the age of this RV and it's presumed value of around $24,000, whether or not a $4,000 repair is worth it. I just recently paid $2,000 for maintenance and repairs.

I think that maybe I'm tired of RV full timing and I'm debating whether it's time to sell the rig and settle down so that factors into it too. If I'm going to keep it another 10 years, hey, do it. But 5? Hmm.

[spierce617]

Maybe try something like this. It is 8000 BTU also.
https://www.costco.com/hisense-smart...000106320.html

[Ray,IN]

Jim, check the value of your MH again. Four years ago mine was valued at $46,800. Last Friday it was valued at $51,950.
The pandemic did strange things everywhere.