Coleman Mach Compressor Failing?

[j-d]

This is a Mach 15 (15,000-BTU) Cool-Only A/C factory installed in 2003. Today, in 95-degree temps, the compressor has been stopping, and needs 15-minutes or so to re-start. This suggests that its internal thermal protection isn't holding. Or, the compressor is running above its design temperature.

I read Run Amps from a Spec Sheet and it's "12.6 Full Load." What I'm seeing on my...harborfright...AC Ammeter is closer to 17. Started around 12 after a cooldown but right now it's in mid-16's, since the sun has dropped a little.

Campground voltage has been as high as 119, no lower than 110, all afternoon.

Unit is clean, and seems to be cooling well. Compressor has a buzz sound in addition to a more normal hum.

The intake filters are recently replaced, but I can change them again. Can also install my new backup capacitor.

Anything else?

Should I be A/C shopping?

[j-d]

Chris, I agree! The plastic they use is really durable. But the Foam, so insignificant in the box (if it actually WAS in the box...) is a critical part of the System.

At this time, I don't plan on doing anything but the "noodle" fix till next time I have to be in there, which, Lord Willing, we be a long time.

For those of you watching at home, it appears the two Foam "wedges" would be about 1" thick where they glue/tape to the Condenser Frame, then starting around 1" deep and tapering out to about 2" at the bottom. About 11 to 11-1/2" long (tall). The Swim Noodle is about 3" diameter so a lot of squeezing, but the foam's not very dense and there's about a 3/4" hole down the middle. Pretty easy to crush.

[Chris_Bryant]

The good thing is it works, the bad is- they really need to look at that "lifetime warranty"- it does no good if appearance is all the warrant- function should be as well, and those foam strips are essential to function.

[westend]

You can use packing foam and 3M spray adhesive to install the correct fit of foam. Of course, if the pool noodles are working, why fix it?

[j-d]

Well...Tech Support says the foam pieces are Not Available. Not sure how they could be anything BUT available inasmuch as they still sell that shroud and the current install instructions include the foam.

Anyhow, we took a 10-day trip using the A/C with a "roof" I made from sheet plastic. The system ran without incident in the same heat/humidity that had been shutting it down before.

I've since made my own foam pieces from a swim noodle as shown here:


In this pic, they're attached the top corners of the condenser frame with sheet metal screws and fender washers. The tore off when I tried to install the shroud. What I ended up doing, was tuck the two noodle pieces horizontally under the bottom edge of the shroud. Then I placed the shroud (Tuffmaxx, I don't know if a Coleman shroud will let you do that!) in place rear/condenser end first. I then worked the pieces up to vertical and rolled them to vertical at the edges of the coil. Rolling should be done so the rolling surface is the one against the coil face, and the dragging action is against the shroud.

Time'll tell, next trip...

[j-d]

Called Airxcel today. I'd sent a "contact us" inquiry and hadn't heard back. On the phone, Parts dropped me quick as they could and transferred to Tech Support. Tech wants to send me the parts but they couldn't find part numbers. Said they'll mail them if they can, call me if they can't.

Unit has NOT shut down on overheat and we're four days into a trip where it's upper 90's and very humid. No shroud on the unit, only my little "roof" over the blower motor. So... we'll see what happens at Airxcel. Meanwhile...

...Case Pends...

[Chris_Bryant]

j-d wrote:
!!! NO !!! Chria I do NOT. It didn't have them, back when I replaced the OEM Coleman shroud with a MaXXair "TuffmaXX" shroud. Your pic looks like our Tuffmaxx. Don't think the older Coleman we had, used them either, but too long ago. What can I use in a pinch? Thinking that foam flex insulation for water and home A/C tubing...

That should work- I would bet that Lowes has foam for garage doors that would as well. I bet if you contacted them they might send the right strips out-
http://www.airxcel.com/maxxair/contact-us.

[SoundGuy]

j-d wrote:
The Big Two are Coleman Mach and Dometic Brisk II. Probably a Ford/Chevy kind of debate, but is one really better?

If Brisk was actually quieter in operation than our present Mach, I think we'd go Brisk.

Over the years I've owned a Carrier AirV, Dometic BriskAir, Coleman Mach 3+, and now have a Dometic Brisk II on our current trailer - no way is the Brisk II any quieter than any of the others, despite what Dometic may claim.

[j-d]

!!! NO !!! Chris I do NOT. It didn't have them, back when I replaced the OEM Coleman shroud with a MaXXair "TuffmaXX" shroud. Your pic looks like our Tuffmaxx. Don't think the older Coleman we had, used them either, but too long ago. What can I use in a pinch? Thinking that foam flex insulation for water and home A/C tubing...

[Chris_Bryant]

j-d , do you have the foam strips (D) installed to keep the air from recirculating? If those are not in place it will overheat and overload.

[j-d]

UPDATE...

The A/C ran fine for the rest of the trip we were on when the compressor started shutting down.

Latest is... I've had it running several days getting ready for another trip. It's been nearly 100, and the compressor shut down toward late afternoon for two days. I've been wondering if the shroud was restrictive. Took it off and A/C kept running for two days, similar weather. Yesterday I made a "roof" for the A/C using a 20" by 24" piece of plastic. Keeps direct rain off the blower motor. Been running steady using the "roof." Starting to look like the shroud has a negative effect on the A/C.

[MEXICOWANDERER]

FOOLPROOF

FIX

[j-d]

Cleaned the coils this morning using spray cleaner and water spray. Kept water out of interior with deflector (license plate) and towel.

Always worth doing but the coils had no pieces of debris, only some dust that formed a little muddy spot on the coach roof.

System ran normally the remainder of yesterday, last night, and so far all day today. I think that with air temperature nearly 100 and enough humidity to put heat index around 130, system reached its limits.

That said, the aluminum fins on the condenser coil are starting to flake away. Sixteen years and a many beachside campgrounds have given salt air its chance.

So, need to consider a new A/C soon. To me that's within a year.

The Big Two are Coleman Mach and Dometic Brisk II. Probably a Ford/Chevy kind of debate, but is one really better?

If Brisk was actually quieter in operation than our present Mach, I think we'd go Brisk.

Advent? Nope, don't think so.

New Atwood? Don't know enough about it...

[j-d]

Chris, I'm a believer in your old blog post Rooftop A/C Tuneup. Is there any way to bring it up to the top/front somehow?
Was going to wait till we get home, but I think I'll go after it tomorrow right in the campground.
Now that it's sun down, the unit is cycling at about 78...
...BUT... the temp control knob is way "Cold" from where we usually have it for that temperature. Wondering if the thermostat is failing. Feels Gritty when I turn it to set. Where can I get 6701-3401 T'Stat? Is that the current part number? Oh, My! Amazon...

[Chris_Bryant]

Clean the outside fins.