Coleman Basement A/C

[DAN L]

Originally Posted by Forkyfork

Does anyone know if the bearings can be lubed without pulling the unit?

Nope
Duner on this forum has info about the bearings.

[doorguy]

Have you contacted River City RV Repair in Sacramento? George (owner) worked on ours in 2015, very knowledgeable.

[Jsout]

I too am at my wits end, (didnt take much). I purchased an 03 Adventurer about 2 weeks ago. The a/c unit will not cool the rv to a comfortable temperature. Ive read all threads etc. System seems to be working fine with both compressors running as designed. We even took it out friday, cleaned and added very little freon to it. Air duct temps are from 60-70 degrees. Called coleman and they said a 20 degree split is all i will get. I realize its hot and humid here in S Georgia but this is unacceptable. What are my options (add a roof mount?, try to replace my unit?)

[MutinyGuy]

Originally Posted by Jsout

I too am at my wits end, (didnt take much). I purchased an 03 Adventurer about 2 weeks ago. The a/c unit will not cool the rv to a comfortable temperature. Ive read all threads etc. System seems to be working fine with both compressors running as designed. We even took it out friday, cleaned and added very little freon to it. Air duct temps are from 60-70 degrees. Called coleman and they said a 20 degree split is all i will get. I realize its hot and humid here in S Georgia but this is unacceptable. What are my options (add a roof mount?, try to replace my unit?)

Typically the duct work on these units will leak so if you haven't already checked that would be the best place to start. Put your hand up as far as possible to feel for cool air...maybe pull the rear tail light will give you more access to the duct work.
How many amps are you pulling with both compressors running? I just had major service done on my basement unit and I have a split of close to 30 degrees...of course I am in a very different climate then you! Hot and DRY!

[Jsout]

When we installed the unit back friday I sealed up the elbow joint well but didnt look any further up, unit is pulling about 16 amps on generator and about 23 on shore power. From what i understand the ampmeter doesnt read the second compressor on gen power.

[MutinyGuy]

Originally Posted by Jsout

When we installed the unit back friday I sealed up the elbow joint well but didnt look any further up, unit is pulling about 16 amps on generator and about 23 on shore power. From what i understand the ampmeter doesnt read the second compressor on gen power.

Your amp draw sounds right on....I would look for a leak further up in the duct...they have been known to split open...

[tmw188]

When you are talking split do you mean a temp. difference? Between supply and return? That should be taken as close to the unit as you can. A TD of 30 seems unrealistic.!

[MutinyGuy]

Yes I have checked the temp difference many times with an IR gun and digital HVAC thermometer. I continually get close to a 30 degree split. What can I say. It is what it is!

[doorguy]

One thing that is often overlooked, primarily due to the access, is the ac duct from the unit up the rear of the coach. The 90 deg. elbow duct is mated to a square duct which extends up to a "Y" fitting and splits off to both air ducts in the ceiling that extend all the way to the drivers area. The square duct is folded and seamed on one side only. At this seam, the tape has a tendency to fail and the pressure of the air will force cool air out the seam. You should be able to get under there and with a light, peer up into the cavity and see the duct. You can test the system by running the air and taking a stick or sturdy wire with a light piece of string, yarn or a sliver of paper and run it up by the duct on the seamed side. If you see any movement of the test strip, you most likely have a split seam and you are losing a lot of cold air before it even hits the ceiling ducts.

The access will be tight up there, but it is worth a try in my opinion. Ours had that issue and we were losing a ton of air to the outside. I used a quality duct aluminum duct tape and so far it is holding after two years.

I recall seeing a post on this subject a while back and the gentleman detailed how he was able to reach up and seal the duct. Some coaches in your year range have better access to the duct, i.e., diesels, because the taillight is up high(access behind it) and side access can be gained thru the radiator compartment.

[Jsout]

Got in there yesterday and found about a 2"x10" gap letting alot of air out, got some aluminum tape today so when i get home im going to fix that and look for more, I appreciate the feedback.

[MutinyGuy]

Originally Posted by Jsout

Got in there yesterday and found about a 2"x10" gap letting alot of air out, got some aluminum tape today so when i get home im going to fix that and look for more, I appreciate the feedback.

That would do it!!

[Heating man]

Originally Posted by Forkyfork

Does anyone know if the bearings can be lubed without pulling the unit?

Bearings cannot be accessed without pulling unit. Top has to be taken off to work on them

[tmw188]

Originally Posted by Heating man

Bearings cannot be accessed without pulling unit. Top has to be taken off to work on them

Bearings may be sealed unless you know differently?

[Forkyfork]

Originally Posted by tmw188

Bearings may be sealed unless you know differently?

The OEM bushings(bearings) are brass if I remember correctly. Either way they arent sealed. I went over someone elses tutorial on pulling the unit to replace the cage and motor. they change out the bushings to sealed bearings.

I just couldnt tell if there was maybe an access port to avoid having to pull the entire unit which looks really sucky to just lube some bushings.

[sgtstriker]

Well, I now have cold air flowing. Having followed the suggestions of a number of you folks on this thread I'm having some success.
One more question though.. When on the genny my amp draw meter indicates 17 amps. Shouldn't it be drawing more like 24-25 amps if both compressors are working?

[MutinyGuy]

Originally Posted by sgtstriker

Well, I now have cold air flowing. Having followed the suggestions of a number of you folks on this thread I'm having some success.
One more question though.. When on the genny my amp draw meter indicates 17 amps. Shouldn't it be drawing more like 24-25 amps if both compressors are working?

Yes you should see about that many amps being pulled but I believe the second circuit does not show up in the total amp draw when running on your generator...you can pick up an amp probe to determine what your AC is pulling..you would have to measure each of the 120v ckts to give you an accurate total...that can be done at the ckt panel or where the 120v ckts are terminated on your AC panel.

[sgtstriker]

Oh, OK, so I would need to go somewhere with a 50 amp service? And that would indicate the higher amp draw, assuming that the 2nd compressor has fired off?
I also found that the duct work has some sealing failures. So, I'm getting there...

Thanks.....

[Forkyfork]

So...am i understanding correctly that the units don't run the second compressor unless they are on 50A?

I have a new to me 2004 winnebago and while the unit cooled fine in FL. I only could hear one compressor fire and only see one fire on the amp display on the control panel. Running it draws what you mentioned 17A. Ive only been on 30A and gen power. I thought maybe this unit only had one compressor. Haven't had time to look into it. BTW the fan is around 7-9A alone if you were wondering.

Oh an change your filter if you havent and try to avoid using the high filtration ones. I took a laser temp gun to the ducts when I first inspected the rig and found the filter being sucked into the duct, removed it and it raised the exit temp almost 10*.

[sgtstriker]

Yes, if you are on the typical house electric you only have 20 amps. Your electric management system will recognize that and not even try to fire the second compressor. Apparently if you are on generator it will fire the second compressor but not log the additional amp draw on your monitor. So, you have to check the amp draw via another method while on generator or plug into a 50 amp system to see that the second compressor is running. Keep in mind that the second compressor only starts when the first compressor is failing to bring temps to the requested level, so set your thermostat much lower than the interior temperature.....

[Ray,IN]

Originally Posted by Forkyfork

So...am i understanding correctly that the units don't run the second compressor unless they are on 50A?

I have a new to me 2004 winnebago and while the unit cooled fine in FL. I only could hear one compressor fire and only see one fire on the amp display on the control panel. Running it draws what you mentioned 17A. Ive only been on 30A and gen power. I thought maybe this unit only had one compressor. Haven't had time to look into it. BTW the fan is around 7-9A alone if you were wondering.

Oh an change your filter if you havent and try to avoid using the high filtration ones. I took a laser temp gun to the ducts when I first inspected the rig and found the filter being sucked into the duct, removed it and it raised the exit temp almost 10*.

I've been using Filtrete allergen air filters ever since we bought the coach, despite that warning. I have to change them monthly since they catch so much dirt, but I breath easier and the coach remains cleaner longer.
Mine begins running both compressors whatever amps are incoming, but the Progressive monitor panel will begin turning off appliances when amp-draw nears 80% of circuit capacity until amps fall back below 80%.

If the #1 compressor is not running, neither will #2 compressor.
Here are my bookmarks for Coleman-Mach basement units, hope you find them useful:
Winnebago basement heat pump AC under the coach,removal Airxcel RV Products Service locations basement air conditioner compressor Motorhome RV HVAC Controls - Evans Tempcon Start Device Package for Coleman Air Conditioners 8333A9021: Automotive Basement A-C Removal Procedure-Revised 8-24-2013.pdf Coleman Mach 2 Two TON Plus Basement Air Conditioner W/HP 24,000 BTU 46515-811 Basement A/C Removal & Outdoor Blower Replacement Procedure - iRV2 Forums Replacing the Coleman Mach thermostat with an Ecobee Coleman 46515-811 69859 Two Ton Plus Basement Central Air Conditioner 24000 BTU