Ready to replace basement ac/heat pump

jagnweiner said:

He went back and confirmed that no, mine is the rare exception.  No heat pump

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Interesting. I had no idea there was a version w/o heat pump capability. Although our unit has done very well (except for a week in direct sunlight in Dallas the summer Texas was over 100 every day for a month or more). I have thought time or two about adding a roof air just to get more cooling. Two considerations are that I hate to loose a roof vent, AND I would want it to be ducted through the existing roof ducts. 

jagnweiner said:

Yes, that's what he said.  The electrical is trickier than the ductwork.

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Do I understand that to mean they have connected a roof air conversion to the ductwork?

afchap said:

  Do I understand that to mean they have connected a roof air conversion to the ductwork?

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Yes, they have, apparently multiple times. He looked up the invoice from the last time they did it.  It sounded like connecting to the ductwork wasn't that tricky because it's not too far from the vent openings to the ducts. It was the wiring that was the challenge. Based on John's auxiliary roof air project I'm thinking it wouldn't be too bad to get 120v to the unit in the middle of the coach, but the rear would probably be a challenge.

I would simply run the romex right down the AC ducting to the rear location of the roof AC. The cool air would not harm the romex in any way, and the routing would be simplified. 

I don't know about RV code, but wiring run through a duct in buidings has to be "plenum rated".

Interesting thread, glad you've got things going your way now Scott.

The primary difference (AFAIK) between a heat pump and non-heat pump model is a reversing valve - instead of removing heat in the A/C mode, it removes cold in heat mode by sending the refrigerant in the opposite direction.  There's not that many parts involved (assuming no coil defrosters.)

John Canfield said:

The primary difference (AFAIK) between a heat pump and non-heat pump model is a reversing valve - instead of removing heat in the A/C mode, it removes cold in heat mode by sending the refrigerant in the opposite direction.  There's not that many parts involved (assuming no coil defrosters.)

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I also believe that to be the case.  When we were having our conversation about the heat pump, the tech put me on hold, went out and checked the unit, and came back and said "no reversing valve, so it's not a heat pump."  He just hadn't noticed it before when he was diagnosing the problem.

Turning back to Paul's original question, were I in your shoes I would do the same thing and spring for a new unit if you can find one.  I'm not 100% confident in the longevity of the repair on mine.  The tech said he could tell it has been worked on before, as ports had been soldered into the line for recharging.  I'm just not in a place right now where I want to pour money into a whole new unit, as we might try to upgrade to something a little newer in a few years.

John Canfield said:

Several years ago at factory service in Forest City I noticed a Vectra with three rooftop airs  , I thought this was a prototype or something like that.  When I asked the owner, he simply replied that he "likes it cold."  Okay then.

One rooftop air will not provide enough BTUs for cooling, two might, three for sure but that's a lot of weight up there if you have other stuff installed on the roof.  Also, the roof airs would need to be heat pumps or have heat strips (not very efficient.)

For the DIY guy, I would much prefer to pull a basement air unit than horse a rooftop air off and on the roof.

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At risk of causing this thread to meander further afield, it's not actually that hard to get an AC unit up on the roof.

I replaced both mine.  The first time I had three teenagers to help me, I used two step ladders, put a plank between them as a sort of scaffold, and just hoisted it up in two stages.

The second time I only had one teenager. I used an extension ladder extended and propped up at a good angle.  Placed the unit crosswise on the ladder, put a rope around it and simply dragged it up.  One person on the roof hauling, another on the ground sort of holding the ladder and guiding it up.  I left it in the box so it slid better. When we got it to the roof, slid it off the ladder and cut it out of the box.

I definitely recommend the second method. Took about the same amount of time as typing up this paragraph.

Almost forgot, and the teenagers LOVED tossing the old unit down to the ground.

Somewhere in this thread, someone asked if they actually still sell new basement AC replacement units. Can someone reply with this info or link?  Thanks!

They are built in Wichita,  KS, as they have been for many years. I thought I mentioned that I priced one just a few days ago with a local dealer after email exchange with the mfg'er to get the correct replacement model number. Winnebago quit installing them in new coaches,  but production never stopped.  Check http://www.airxcel.com/coleman-mach/where-to-buy/. They make roof units as well as these 2 ton basement units.

Mosagra said:

..At risk of causing this thread to meander further afield, it's not actually that hard to get an AC unit up on the roof...

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With some planning (I almost always work alone since we have no nearby neighbors) - I can get a roof air on the roof but I'm using my loader and Genie lift - it's still a hassle though.  I removed a 100 pound Datastorm satellite unit off a roof a couple of years ago and even with some help while I lowered it down a ladder, it was a big handful. 

afchap said:

They are built in Wichita,  KS, as they have been for many years. I thought I mentioned that I priced one just a few days ago with a local dealer after email exchange with the mfg'er to get the correct replacement model number. Winnebago quit installing them in new coaches,  but production never stopped.  Check http://www.airxcel.com/coleman-mach/where-to-buy/. They make roof units as well as these 2 ton basement units.

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I think these basement units are used in park models, not sure if they are currently being installed in any RVs.  Winnebago stopped using them when DEF tanks needed to be parked in that basement area and I think the other, maybe primary reason is that 24,000 BTUs (two tons) is not enough capacity to cool a full body paint three or four slide >=40' coach in hot weather.  Two tons was fine in a 35' maybe 40' no slide or two slide coach with white gel coat sidewalls but not with the previously mentioned later models.

Recently purchased my 2000 Chieftain 35U. Basement system was working when I bought it in February... but didn't use it much till just a few weeks ago. Noticed that the OD Blower had trouble kicking on. Basic troubleshooting tells me... Start/Run Capacitor or bad connections are most likely, since with a little manual assistance the blower kicks on.
But, as long as I'm going to have this out, there is an opportunity to check all connections and read all the caps, clean the coils and ductwork. With a new capacitor in hand, I removed the unit and did a full inspection. Now for the fun part...  There is a jumper wire on the #1 Compressor Relay, but none on #2. Hmmm.... Diagram shows the jumper wire on both. Double Hmmmm.... Bit of research and I discover that the Jumper Wire installed on these relays get really hot if the connections aren't solid. It appears the jumper on #2 burned up and the previous owner just ran on 1 compressor. Actually done on purpose. I do all my repairs and cleaning, replace the Jumpers with 10ga insulated wire, replace grounding straps and fire it up. Blower starts right up BTW. Amps go from about 14 to 27 and both compressors chug away.
RV quickly changes from Dry Heat Sauna to 35' long Ice Box.

I wish I could confirm how maintenance issues were done on this rig before I got her, but I have discovered some sort of "workaround" "bypass" or "jury rig" condition on nearly everything but the chassis.

There seems to be a preponderance of poor maintenance practices on RV systems, because people think it's just like a house. We should really start a thread on how to know if your RV mechanic is an idiot.

RPatt278

Haha! Funny, that's how mine was too, burned up jumper and capacitor and starter motor were both fried. The PO didn't bother to repair it and they did something to the water heater circuit somewhere as well. Never did find they did 'cause ended up putting in my own aftermarket heating element and running new power line. Stay with in MC RPatt278  ;D

RPatt278 said:

...I wish I could confirm how maintenance issues were done on this rig before I got her, but I have discovered some sort of "workaround" "bypass" or "jury rig" condition on nearly everything but the chassis....

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That's a real shame and I absolutely detest that sort of thing - owners that are too cheap to keep their equipment in good operating condition.  Unfortunately there's a bunch of them out there. 

Way after we bought our little house I discovered the previous owner that had the house built was too cheap to have plywood or OSB sheathing installed on the outside 2x4 stud walls.  It's Tyveck wrap with a Hardie plank imitation nailed directly to the wall studs.  Unbelievable.  Plywood sheathing adds structural integrity to a building.

John Canfield said:

Way after we bought our little house I discovered the previous owner that had the house built was too cheap to have plywood or OSB sheathing installed on the outside 2x4 stud walls.  It's Tyveck wrap with a Hardie plank imitation nailed directly to the wall studs.  Unbelievable.  Plywood sheathing adds structural integrity to a building.

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That is unbelievable. I can't believe it would pass a building inspection.

John Canfield said:

That's a real shame and I absolutely detest that sort of thing - owners that are too cheap to keep their equipment in good operating condition.  Unfortunately there's a bunch of them out there. 

Way after we bought our little house I discovered the previous owner that had the house built was too cheap to have plywood or OSB sheathing installed on the outside 2x4 stud walls.  It's Tyveck wrap with a Hardie plank imitation nailed directly to the wall studs.  Unbelievable.  Plywood sheathing adds structural integrity to a building.

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Not even any sheathing on the corners?

John Hilley said:

Not even any sheathing on the corners?

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Possibly, that's apparently all of the sheathing you routinely get around here.  Permits? Ha! We have had a kitchen island with no electrical outlets - this is against the National Electric Code (I had to use a diamond saw to make a trench to run some 14/2 w/g.)

Just my own two cents on getting an AC unit on the roof. My hardware store was happy to hoist one up to the top of my rood using their forklift. I'll bet that many other small comminuted stores would be happy to help. Many are great customer and community minded small business owners, and the only thing you need to do is the basic homework so that it's set to quickly bolt down in the lot.

RPatt278 said:

I have discovered some sort of "workaround" "bypass" or "jury rig" condition on nearly everything but the chassis.

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  I bought a classic car a couple of years ago, represented as having had "meticulous" maintenance by the previous owner. First thing I found was a bend hood prop held in place when stowed by a piece of wire. Next thing was a piece of red electrical wire where a cotter pin should have been. I have found many crazy "fixes." My latest repair was to the front suspension. Crazy thing is he bought very expensive parts (coil-overs), and then butchered them with a torch to the point they were a problem. Rather than "meticulous" I have re-termed it "mickey mouse" maintenance.

Hey, I'm back!  Just got my coach back today from the shop after about a 5 week stay due to delays getting it in and then shipment of a new #1 compressor from Wichita. All is well for now. Total bill was about $1500, split pretty evenly between parts and labor. Cranking out cold air, about 22 degrees below ambient.

When i got home, my son asked "Dad,  how long will this repair last?"  I don't know, boy, I don't know.

Ordered a new basement unit yesterday.  After checking several possible sources including a local dealer I contacted  Dyers RV (dyersonline.com) where I recently go a new ATS. Their quoted price was $2288 w/shipping included.  Best I found anywhere else was $2999 before tax or shipping was discussed.