Winnebago Coleman Basement A/C

[prafersno]

I will be the owner of a 2004 Ultimate Advantage very soon. Upon first visit, the basement unit would only blow warm air while on the genny. The MH is in another state so a local family member went to check it out. That being said, I won't be able to answer specific questions about settings or amp draw.

So, I'm trying to learn everything I can about the Coleman Mach Two Ton Plus unit in my coach. I'm gambling that if it's not just some setting that wasn't right and it actually works, that it will be the relays or caps. It will be odd if both compressors have failed, right?

If it is the compressors, what is stopping me from changing brands as long as the specs are within a tolerance?

I found a $143.00 compressor with these specs:

Specs Applications:
Voltage: 115V, 60Hz, 11.2 Amps
Refrigerant: R-22
Evaporating Temp. Range: -15 to 12°C / 5 to 53.6°F
Condensing Temp: 65°C / 149°F
Return Gas Temp: 35°C / 95°F
Discharge Temp: 115°C / 239°F
Capacity: 13,315 Btu/h
Displacement: 19.1 cc/rev

https://iscsales.com/item/panasonic-...hoCbScQAvD_BwE

Then, what are your feelings of switching to R-407c or another R-22 replacement refrigerant?

[Ray,IN]

I have a model 6535 Coleman-Mach unit, which is no longer available; instead the alternative is the 6515 and conversion kit for ductwork..
The old units used R22 refrigerant which is NLA. Switching to R134 refrigerant requires changing out compressors.
Were it me, I would plan on replacing the OEM unit with the 6515 replacement, which is close to $4K, and price MH accordingly.


Another thing to check out is the Cummins exhaust manifold. They are prone to breaking due to supporting the entire load of the turbo-charger and associated piping. If the lift pump is leaking it will dribble fuel onto the starter, then drip onto the floor after shutdown.
That's about it for things to look for with the W Ultimate series of MH's. They were the most luxurious, limited production, MH Winnebago built between 1999 -2004.5.

[2004Horizon]

Sounds to me like you are looking to negotiate. Okay. Can't blame you, so here goes:

1) If the compressors are okay then you should be okay repairing this basement AC.

2) Just because the fans runs that does not mean the compressor are okay.

3) You might just need a couple of hard start kits ($60 ea.) and you need 2.

4) If the compressors will not start, your basement AC is almost junk, and you will have to go to a salvage yard to buy another one... and from everything I have read you don't want to deal with any conversion or customizing your air handler. to make it all work with your existing duct work. (Which probably leaks, BTW, if you don't get good/cold air out your roof vents.)
Note: After owning an RV with a basement AC I will never want to own a rooftop AC, because I hate listening to the noise of a rooftop AC.

Your Ultamate Advantage is "top of the line" for its day so my guess is that you have Panasonic compressors and not Tecumseh, which are slightly smaller, but can be replaced, whereas I have never come across a Panasonic compressor replacement for your Coleman Mach Basement AC. (Still waiting for leads on this if anyone has one. )

But I digress. I love my basement AC. And in your case, there is a 50/50 change you can get your basement AC running by just doing a tune-up the previous owner never did. (Starting with new hard start capacitor and motor starter, aka PTCR.)

You may need new relays and run capacitors (all relatively cheap) and worst case a control board.

f you go to a shop you could be looking at anywhere from $600-$1500. If you learn how to tune-up your basement AC, and don't need a control board, you can probably do so for $250 in parts. ...Also assuming you did not here any squeals coming from the fan when it was running; and as mentions your compressors will start.

Good luck. And don't worry about your options. Take the leap. It's obvious you are picking this coach up for cheap and I know things will work out.

There is lots of information on this forum that will help you DIY and same money. I.e., if it was me, because I know what to do with a basement AC, I would look at this situation as an opportunity more than a big risk. And I doubt the seller sees it this way. Just try not to get too greedy.

Offer the guy a fair price knowing there are risks with basement AC; and might I say, I would feel the same way about the NEVER-COLD refrigerator it this rig has not been upgraded to a residential refrigerator, which is a must in my opinion too.

[2004Horizon]

Here's some reference materials on your basement AC:

[Thomm85n]

We have a 2007 National RV 36’ Pacifica with the Coleman Mach basement air. THEY SUCK! I’ve tried electronic capacitor changes and other fixes as I am a retired FAA Licensed and Certified mechanic with certification for engines and airframes. With all my knowledge and training I’d remove that basement air and toss it to the junk man! We ended up removing 2 fantastic fans and installing inexpensive roof AC’s. That basement are is. DEAL BREAKER! The cooled air is supposed to be pushed full length of RV (there’s 2 plenums) and adjust aiming air with eyeballs that turn ugly yellow, crack when older because of the CHEAP plastic crap they are made of. You will also end up having trouble with you LP gas 120 fridge and there’s a lot of wood framing in those old coaches. You will hate yourself for spending money to buy and the needed maintenance. Unless you are an RV mechanic who could build your own RV, I’d steer clear. I don’t think Coleman Mach even makes them anymore. To remove unit they come out the BOTTOM of the Coach and the coach has to be raised a little. There’s a good reason the seller wants you to have and enjoy their expensive mistake. You’ve been warned. Still got your money? See what the insurance company would pay you when it’s totaled. Then add blood sweat and tears. Blood smells like gasoline! Old rubber lines, seam leaks eventually going down walls to warm and wash the mice, soft floors means water damage every time. A pig with lipstick is still … a pig. And don’t forget the old mildew and algae and mold.

[prafersno]

Originally Posted by Thomm85n

We have a 2007 National RV 36’ Pacifica with the Coleman Mach basement air. THEY SUCK! I’ve tried electronic capacitor changes and other fixes as I am a retired FAA Licensed and Certified mechanic with certification for engines and airframes. With all my knowledge and training I’d remove that basement air and toss it to the junk man! We ended up removing 2 fantastic fans and installing inexpensive roof AC’s. That basement are is. DEAL BREAKER! The cooled air is supposed to be pushed full length of RV (there’s 2 plenums) and adjust aiming air with eyeballs that turn ugly yellow, crack when older because of the CHEAP plastic crap they are made of. You will also end up having trouble with you LP gas 120 fridge and there’s a lot of wood framing in those old coaches. You will hate yourself for spending money to buy and the needed maintenance. Unless you are an RV mechanic who could build your own RV, I’d steer clear. I don’t think Coleman Mach even makes them anymore. To remove unit they come out the BOTTOM of the Coach and the coach has to be raised a little. There’s a good reason the seller wants you to have and enjoy their expensive mistake. You’ve been warned. Still got your money? See what the insurance company would pay you when it’s totaled. Then add blood sweat and tears. Blood smells like gasoline! Old rubber lines, seam leaks eventually going down walls to warm and wash the mice, soft floors means water damage every time. A pig with lipstick is still … a pig. And don’t forget the old mildew and algae and mold.

Try as you might, I'm not gonna tell you where is it. Just so you can steal it out from under me!

No, seriously. Thanks for the heads up. I'm going into this with very low expectations. All I Must have right now is a strong chassis (and the central vacuum to work!)

AND a residential fridge will be on the long list, but in the mean time I don't have any plans to use the LP side of that unit.

[2004Horizon]

Thomm85n: Seriously, with all your creds you couldn't get your Basement AC to work? ...That's a shame!

[UFO Pilot]

My basement air is 16 years old and still going strong. We love it.

[Ray,IN]

Originally Posted by Thomm85n

We have a 2007 National RV 36’ Pacifica with the Coleman Mach basement air. THEY SUCK! I’ve tried electronic capacitor changes and other fixes as I am a retired FAA Licensed and Certified mechanic with certification for engines and airframes. With all my knowledge and training I’d remove that basement air and toss it to the junk man! We ended up removing 2 fantastic fans and installing inexpensive roof AC’s. That basement are is. DEAL BREAKER! The cooled air is supposed to be pushed full length of RV (there’s 2 plenums) and adjust aiming air with eyeballs that turn ugly yellow, crack when older because of the CHEAP plastic crap they are made of. You will also end up having trouble with you LP gas 120 fridge and there’s a lot of wood framing in those old coaches. You will hate yourself for spending money to buy and the needed maintenance. Unless you are an RV mechanic who could build your own RV, I’d steer clear. I don’t think Coleman Mach even makes them anymore. To remove unit they come out the BOTTOM of the Coach and the coach has to be raised a little. There’s a good reason the seller wants you to have and enjoy their expensive mistake. You’ve been warned. Still got your money? See what the insurance company would pay you when it’s totaled. Then add blood sweat and tears. Blood smells like gasoline! Old rubber lines, seam leaks eventually going down walls to warm and wash the mice, soft floors means water damage every time. A pig with lipstick is still … a pig. And don’t forget the old mildew and algae and mold.

You have so many misconceptions in that reply, I'll not attempt to correct them. Then again, perhaps you are tolling?