Air Conditioner (Coleman Mach) Not Working - Advice Needed

[vagabonds_moon]

Hey Folks - I am looking for some advice. About 1.5 months ago the a\c stopped working on my rv - it's a coleman mach. I am located on the Gulf Coast, and there is no shade from the sun on my rv, so it's getting very hot (low-mid 90s at the hottest part of the day) so I'd like to try and resolve this:
The a\c hums when I turn it on, but doesn't come on and blow air -
I had a guy come out and look at it - I got on the roof with him to see what he did: he cleaned the fan shaft with a brush, and sprayed it with white lithium grease. Also, he sprayed the compressor with coil cleaner. He then asked me to get down and go in and cut the a\c on - it did come on and function normally. He then said to turn it off again, because he'd put some product on it that needed to dissolve, to wait about 3 hours then I could use the a\c. I waited the 3 hours, then... the a\c once again did not work. I called the guy, but never could get him back out to look at it again..

Anyway, I am wondering if there's something I could do myself, to get the a\c running - if he could do it, why can't I, i'm thinking.
I did get on the roof a few days ago and try to spin the fan by hand, it does not spin freely. I wonder if I were to spray the shaft with lithium grease and turn it by hand, could I get it running.

Maybe the fan motor just needs replacing, I am not skilled in these things and so came here for thoughts. Still I wonder how the guy got it running, when I called him later, he said maybe we should have let it run a little longer before I turned it off to sit for a few hours.

Anyways, any thoughts are appreciated

 

[Arch Hoagland]

Mine would occasionally do the same thing. I would go up on the roof and spray WD40 on the bearings. NOT grease.

I would also set the fan speed to high and remove the filter so I could give the squirrel cage a push to get the motor running.

Once it starts running let it run a good half hour before shutting off.

I would then exercise mine every couple weeks to keep it going.

Last year it started making a rubbing noise and  I took it in for service and they found the squirrel cage set screw had come loose and the cage had moved far enough to start rubbing on the housing.

They moved it back and it's been fine ever since.

 

[ChiefM]

Yes use WD40 on the bearings and spin the motor while you spray. Don't be frugal you won't hurt anything. Also take a look at the capacitor. They are fairly inexpensive and if it looks swelled i'd replace it. The tech may have spun the motor by hand to get it to run while you were inside the coach. It is a fairly simple system so I'm sure you can repair it yourself.

 

[SWFL FlyFisher]

Also take a look at the capacitor. They are fairly inexpensive and if it looks swelled i'd replace it. The tech may have spun the motor by hand to get it to run while you were inside the coach. It is a fairly simple system so I'm sure you can repair it yourself.

Agreed.  The hum makes me suspect the capacitor as well.  New ones usually run around $25 or so online and are easily be replaced in just a few minutes.  WARNING - If you've never dealt with capacitors before, either do some reading/video watching or find someone who knows how to work with them as they can give you a good shock if not discharged.

 

[ChiefM]

The hum gave it away to me too. My mom in-laws house AC was not working 2 weeks ago and it was doing the same thing. A free estimate from the AC repair guy says 900 to 1000 to repair it. I replaced 2 bad capacitors for the fan motors and I also bought the cleaner to clean the coils for less than 100 out of pocket.

 

[keymastr]

The fan motor should spin freely. It needs replaced. Take the old one to Grainger for a replacement, they are usually in stock and reasonably cheap. Only minutes to replace. Had to do the one on my house a couple years ago, fan motor and new cap was about $200. Weigh the cost against a brand new AC. If it is more than 15 years old I might consider full replacement.

 

[vagabonds_moon]

Thanks folks for the thoughts

I have a question: has anyone ever built some sort of a chassis or cage etc. so that a window a\c unit can fit into one of the rounded pop-out type of windows that are common in campers? I was thinking if I could get a window unit in, it'd help out (even if I do get the rooftop unit fixed).

Due to the rounded shape of the pop-out type window, the window kit that comes with an a\c wouldn't work. If I managed to build one, it wouldn't look pretty, but that's about my last concern at this point

Question 2:
Does anyone know a good resource for finding a mobile rv technician? I have called around town to the rv places and they tell me they know no-one who does mobile service

Thoughts appreciated

 

[Arch Hoagland]

Call all the local RV parks. They will know if there are any mobil techs.

The RV repair places probably wouldn't send your business to another repair person. They want you to come to them.

 

[vagabonds_moon]

I am thinking to try to get in a window unit - I thought maybe to try something like this:
http://www.myoldrv.com/wp-content/uploads/2010/06/009.jpg

The thing is, my window is a pop-out type window (or exit window I guess it's called) it has two clamps that shut the window. I'd need to remove the brackets that hold those clamps (they are riveted in) as the space between them is only 14.5 inches, and I doubt there's an a\c of that length. THat, or sit the a\c on top of the brackets, but that seems like a bad idea

Thoughts?
thank you

 

[Larry N.]

I doubt the window area has the strength for something like that, and you certainly don't want to replace an emergency exit with one, since in case of fire or other problems you might be left with no way out.

 

[BoomerD]

We went through this 3 years ago when we got our 2004 Winnebago. The shaft had "rusted" in the housing. Some WD-40 and a pair of vice grips freed the shaft, the shop ordered the upgraded hard-start capacitor kit for it...when we went back to have them installed, they found out the better caps had already been installed. :shrug: Not sure why they didn't see that before they ordered them...

 

[beaverfever]

do not use wd-40 on motor sleeve  bearings it is not a lubricant. only use 10 or 20 wt non detergent turbine oil. no 3 in 1 or sewing machine oil as they have cutting agents in them. best to stop by a electric motor shop and pick up a "zoom spout oilier'

 

[vagabonds_moon]

I went and bought a new fan motor today - in the morning early, just after dawn, i'm gonna try and fix it. I watched the following video, where the a\c unit is quite similar to mine:

https://www.youtube.com/watch?v=doJ_oD18lZs

Only thing is that when I go to do the wiring, I don't have wirecutters, just a boxcutter, I'll have to use it to cut and strip 3 wires, I guess that's doable?

Thanks again for thoughts

 

[Arch Hoagland]

Doable for sure. Let us know how it turns out.

 

[vagabonds_moon]

One thing im wondering about - the capacitor. There are 2 wires from the fan motor that I'll have to slot in to the capacitor. This ac hasn't been ran regularly in about 2 months, in fact I guess it hasn't ran much this year so far. But I have switched it on for a few seconds here and there, most recently a day or so ago (wishful thinking I guess).

I am wondering if the capacitor poses any danger to me? I will have the camper completely unplugged when I go to work on it

Thanks again  ???

 

[Alfa38User]

Removing the old one can be a problem as a capacitor can retain quite a charge. Simply short the two leads together with a jumper wire before trying to remove it. The new one will not be a problem.

 

[irishtom29]

do not use wd-40 on motor sleeve  bearings it is not a lubricant...

Despite the frequent online claims to the contrary WD-40 is in fact a lubricant. It might not be an ideal lubricant but a lubricant it most assuredly is.

 

[beaverfever]

WD-40 isn't actually a true lubricant. WD stands for "water displacing" and its main use is as a solvent or rust dissolver. The lubricant-like properties of WD-40 come not from the substance itself, but from dissolving components.  ? it can help clean up rust or other grime.
i made a very good living selling hvac motors to people that used wd-40 to lubricate their motors.

 

[vagabonds_moon]

I've got a question:

This morning when I went to start, I chickened out  :-\

Though I've been on the roof a couple times briefly, I couldn't get myself up there to work on the a\c - the roof seems "soft" as in, when I push down on the roof with my hand, it depresses downward.. maybe that's normal? I don't know, I don't have the experience to know the difference. This is an 05 model fleetwood
Thoughts?

 

[Boonieman]

My roof has a little ?spring? or give to it as well. I?m like 225 pounds, but I think you will be ok. Cudos to you for trying.