put a roof a/c unit on

[workinrvers]

We have been having trouble with the basement a/c unit in our 02 Journey for quite awhile now. Tried all the "easy" fixes (new capacitors etc.) but we could never get more then luke warm air to blow. The unit does not have the heat pump option and we were tired of throwing money at something (when we could even find someone to work on the thing!) when we could put a brand new unit on the roof. We bought an Atwood 15,000 unit that is actually rated 18,000 and is also a heat pump, plus it has a two year warranty.
I ran the wiring from the living room and the bedroom vent back through the existing a/c duct, into the back cap and exited the duct near the basement a/c. Since there are two separate circuits for the basement air I unhooked it from the old unit and used those feeds to get power to the roof for the new living room unit plus I have the extra wire dead ended (with the breaker turned off) at the bedroom vent for a 2nd roof unit if we decide to install another one sometime in the future.
The hardest part of the install was getting the 100 lb a/c unit on the roof but with the help of a friend we "got er done".
The Atwood is pretty quiet and we really like the heat pump option to take the chill off.

Phil

[CJBROWN]

Cool. (no punn, LOL)

What years had the basement air? I've never heard anything good about them other than there was no unit on the roof.

[cydonia-jacc]

I'm about to replace the rear roof A/C unit. How did you get the unit up on the roof?

[workinrvers]

Originally Posted by cydonia-jacc

I'm about to replace the rear roof A/C unit. How did you get the unit up on the roof?

Curt,

We put an extension ladder up to the side of the motor home and tied a small diameter rope around the a/c unit wrapping it around both it's length and width. One person on the roof supported and pulled the a/c using the rope while the other pushed/slid the a/c ahead of them while climbing the ladder. My DW and I had done this before when adding an a/c to our 5th wheel, takes a little grunting and groaning but it works.

Phil

[workinrvers]

Originally Posted by CJBROWN

Cool. (no punn, LOL)

What years had the basement air? I've never heard anything good about them other than there was no unit on the roof.

we bought our rig used and it never did work like I thought it should and I'm not sure why it didn't have the heat pump option when almost every other one I have seen have them.
I have heard people say how they want to keep the "clean look" of the roof that a basement air gives but I really don't care, would rather be cool.
We also had a difficult time finding anyone that would work on it, several here on the forum said to call home a/c guys but none I called would even come out once they found out it was in an RV. Most of the RV dealers said they didn't have a tech "qualified" to work on anything but the roof units. That left us with mobile RV techs and their charges start at around $100 to just come to the rig and climb from there. Once they work on it for an hour or two and maybe replace a part you already are paying more for the one service call then I paid for the new roof unit.

Phil

[olfart]

On my '98 winne - last year replaced the front roof a/c unit. I just ordered rear roof a/c unit. Age is the factor in mine going back. Compressor failures. The units cost approx. $700 a piece. And put it up on the roof with the help of a bobcat loader.

[edgray]

Originally Posted by CJBROWN

Cool. (no punn, LOL)

What years had the basement air? I've never heard anything good about them other than there was no unit on the roof.

WBGO used the "basement" air on "most" models for quite a few years-I don't when they started using them, but I do know the LAST model year for ANY model was 2010. Lucky me-NOT. Even when WBGO was still using the basement units on "most" of their production, there were a few "lower" level models that just got one roof air.

My basement air unit works so good I now have a roof-top unit in place of my kitchen roof vent fan to make the coach livable in summer.

[CJBROWN]

Wow, that is horrible. I heard they were bad but you never know, sometimes people exaggerate.

We have the one larger roof air unit on our shorter coach, 4kw gen, 30a shorepower. It's always been fine but this last trip it wasn't doing it's job so when I got home I did some internet sleuthing on it and found a few common issues with roof air units. I'll share here in case we have any lurkers besides the basement unit owners.

1. The insulated divider between the inlet and outlet has to be COMPLETELY sealed - air tight. Otherwise the unit just recycles itself. I found gaps at the unit/roof seal - taped everything really well with high-end duct tape. It seems to pump out twice as much air now.
2. there are four mounting screws that tightens it to the roof. If it's loose the seal is loose and the unit is loose. I got a few turns out of all of them to cinch it up tight. IT's super quiet now.
3. The condensor coil can get dirty especially if you're not diligent about keeping the pre-filter washed out. We have run in pretty dirty environments from time to time and the unit is 10 years old now and I've never done anything with it. So I vacuumed the front of the coil and quite a lot of dirt came off of it. It should look like shiny metal, not dirt-tan color. Seems to cool much, much better now. I was surprised that the spec shows about a 20degree drop from inlet to outlet. No wonder it's never ice cold. Will certainly cool off the coach enough to be comfortable though.

And there was some flashing from the unit base housing that protruded into the intake opening by about an inch - trimmed that off with a sharp knife. That was about 8 square inches of blockage in the inlet area. I figured it couldn't hurt, just let it pump as much air as possible.

I have a ducted system and the vent louvers need to be set for least resistance. Directing them is less important than getting max flow. The duct inlets at the AC unit are really not very big. Shame they didn't maximize the volume. I switched the fan on with the rear cover off and it pumps out a LOT of air. Pushing it through the ducts diminishes it a lot.

Seems to be working as new again. Happy campers!

[edgray]

Originally Posted by CJBROWN

Wow, that is horrible. I heard they were bad but you never know, sometimes people exaggerate.

You can find MANY owners with basement AC that LOVE theirs.....I just got a bad one. WBGO repaired it under warranty, but then when it failed AGAIN, WBGO said "sorry, our 1 year warranty is over" and the AC maker (RVP/Coleman) refused to honor their 2 year warranty based on their claim that the WBGO dealer who "fixed it" the first time was not on their "approved dealer" list. What a piece of junk, made by a company with questionable ethics, IMO.

[workinrvers]

Originally Posted by edgray

My basement air unit works so good I now have a roof-top unit in place of my kitchen roof vent fan to make the coach livable in summer.

sad but true.

We had a free standing unit to "supplement" ours but it just kept getting worse to the point the portable was the only thing blowing anything that resembled cool air.
I'm sure ours could be repaired but the whole issue is "at what cost". Talked to one owner who, over the years, had spent several thousand dollars on various repairs to his a/c and it would work for awhile and then he would be calling another repair man. I just decided that a new unit was the best for us seeing as I could install it myself and it would be under warranty, for the first two years anyway.

Phil