DIY Motorhome AC Replacement: Feasibility, Challenges, and Key Tips

[jymbee]

Ok, to be clear not exactly DIY rather DIYWSPTM "Do It Yourself With Smarter People Than Myself".

I have some friends who although not RVers are quite skilled at mechanical & electrical type work and would be willing to help. I've asked around at some RV service shops I've used before for other project and gotten some pretty steep quotes.

No doubt there's a number of folks here who could easily do a job like this and perhaps have done so in the past. In searching around one challenge right away people doing this face is simply getting the new unit up (the old one down I assume would be easy). Not problem in this case as I have forks for the tractor which would make that part not a problem.

Any input as to what issues I might be facing with such project appreciated. Our RV is a 2012 Fleetwood Bounder 33C.

 

[Arch Hoagland]

Well first you have to get the two feet of snow on the roof off.

 

[John From Detroit]

You are looking at a fairly heavy "Box" to get up on the roof. but 2 men can do it .

The job. if you are doing same/same replacement is very easy. generally, 4 screws and 4 bolts and some wires is all there is to it.

That said what is easy for me is impossible for many as I keep finding out in the radio world.

 

[Utclmjmpr]

An extension ladder,, rope,, and two people will do the trick.. I have done two and it isn't that hard..>>>Dan

 

[workinonit]

The biggest challenge for me was getting the unit in place without damaging my roof membrane. But...I did my by myself. I do have a tractor and forks so getting the unit up there wasn't hard. That would be the main challenge without something to lift it. I added a third unit so I didn't have one to take down. If it's a like for like the rest should be easy.

 

[Domo]

No one mentioned gaskets, butyl rubber, self-leveling sealants, etc. Just thought I'd mention that those are all extremely key to a leak-free installation and need to be researched and obtained.

Read the instruction manual twice, please.

Don't forget the pizza for the folks that help.

 

[Gary RV_Wizard]

I think it's a straight-forward job if the replacement is an identical model. In your 2012 Bounder I'm guessing you have a ducted a/c and a wall-mounted thermostat. Maybe two separate cooling zones on a single thermostat? And is it a heat pump or a vanilla a/c (cool only)? Any and all of those can add complexity or not, depending on the compatibility of the new unit.

Then there is the mechanical logistics part. A bulky, heavy object to remove and replace. A fork lift is really handy, but an extension ladder and a rope will do, sliding the old one down and the new one up. You will need a helper.

As was mentioned, make sure you have all you need before you start. The gasket that fits between the upper unit and the roof, some roof caulk, and hand tools such as wrenches & sockets, screw drivers, spare wire connectors, etc. Plus something to lay on the roof to protect it from tears or gouges.

If the replacement is not the identical model or a certified compatible replacement, be prepared headaches in matching up to ductwork and getting the wall thermostat controls to work properly. Especially in a multi-zone system with heating as well as cooling. There will be a zone controller circuit board, probably with switches to set interface parameters, maybe wiring to interact with the furnaces, and so on. Make sure you have instructions and wring diagrams if any of those things are part of the job. That's where hiring a pro may be the better choice.

 

[jymbee]

I think it's a straight-forward job if the replacement is an identical model. In your 2012 Bounder I'm guessing you have a ducted a/c and a wall-mounted thermostat. Maybe two separate cooling zones on a single thermostat? And is it a heat pump or a vanilla a/c (cool only)? Any and all of those can add complexity or not, depending on the compatibility of the new unit.

Yep, you guess correctly. If I search ChatGPT for "need information about the air conditioner on our 2012 fleetwood bounder 33c" it gets me a pretty clear description of what I'm looking at. The rear AC unit does have a heat pump function which I'm reading that basically it's the same as units w/o that function but with some added features that allow it to be used for heat in moderately cool temps.

Then there is the mechanical logistics part. A bulky, heavy object to remove and replace. A fork lift is really handy, but an extension ladder and a rope will do, sliding the old one down and the new one up. You will need a helper.

As I mentioned in my initial post, I have forks for my tractor that would make getting it up there pretty easy.

If the replacement is not the identical model or a certified compatible replacement, be prepared headaches in matching up to ductwork and getting the wall thermostat controls to work properly. Especially in a multi-zone system with heating as well as cooling. There will be a zone controller circuit board, probably with switches to set interface parameters, maybe wiring to interact with the furnaces, and so on.

It seems to me getting the exact same model AC, as you mention, would be the only way to go. In that same ChatGPT thread it described how to get specific information from the plates on the unit itself. I would be very leery about any claims of a unit from another manufacturer that say it's compatible. Given the time & expense involved, not something worth taking any unnecessary chances.

Make sure you have instructions and wring diagrams if any of those things are part of the job. That's where hiring a pro may be the better choice.

Well... you make a number of good points. Points that have me just a bit less enthusiastic about trying to do this myself. I can just imagine some kind of "obstacle" along the way (my typical experience in many such ventures) and then what?

I'll continue to do some investigating. Thank you very much for your insights!

 

[SargeW]

You may be able to save yourself some cash by shopping out the unit yourself, having it delivered and you could put it on the roof with your tractor. Then you would just need some mobile guy to install it. It should cut down on labor hours for the install. The mobile guy would supply all of the extras needed for the install (as part of his bid).

 

[jymbee]

You may be able to save yourself some cash by shopping out the unit yourself, having it delivered and you could put it on the roof with your tractor. Then you would just need some mobile guy to install it. It should cut down on labor hours for the install. The mobile guy would supply all of the extras needed for the install (as part of his bid).

Hmmm... interesting thought. Unfortunately, given our relatively remote location at home, I've not found a mobile repair outfit I could call. The one dealer we have used in the past for other issues could do it but doubt they'd go along with me buying it given what they would charge me over/above what they paid for it.

But definitely something to keep in mind.

 

[Jackiemac]

Ultimately if you do it yourself with direct replacement (that you know works?), and it doesn't work on rig, then you can take it to your dealer for "repair".

Still might work out cheaper?

 

[jymbee]

Ultimately if you do it yourself with direct replacement (that you know works?), and it doesn't work on rig, then you can take it to your dealer for "repair".

Still might work out cheaper?

Oh sure, while they're talking about me behind my back: "Wow, what an idiot. I can't believe he messed this up that bad! We'll have to charge him big bucks to fix this mess".

 

[Edd505]

depend on your mechanical ability my son just did his last summer. Might need help to get the units up and down.

 

[Kirk]

Oh sure, while they're talking about me behind my back: "

I am retired from a customer service position of 32 years and while it was not RV related, I have made many service calls that were to resolve problems that were caused by the owner while saving money. I agree with everything in Gary's post #7, but the catch is that what I may consider to be quite simple and easy, another person might find it difficult or impossible. I have known RV owners who did replace a roof air conditioner themselves without any problems. I also know a career RV tech who has made calls to correct mistakes owners have made when replacing it themselves. My friend said that most of those calls were relatively simple and not too expensive, but he also said that he has twice seen an a/c with major damage due to miswiring. Is the savings worth the risk? Only you can make that call.

 

[Rene T]

It is a fairly easy job if you have even just a little bit of mechanical background. I’ve done a couple in my days. I would do it with 3 people total. Once you stick the roof seal on the bottom of the AC, (the seal has one sticky side) it will take two guys to lift it and set it in place. A third helper on the inside the RV, directs you if you need to position it so it is centered in the hole.
When you install the four corner tie down bolts, do not over torque them. I think the torque is in inch lbs. after the unit has been in for a month or so, go back a retorque the 4 fasteners again. Once again, do not over torque them.

 

[gwinger]

The biggest challenge for me was getting the unit in place without damaging my roof membrane. But...I did my by myself. I do have a tractor and forks so getting the unit up there wasn't hard. That would be the main challenge without something to lift it. I added a third unit so I didn't have one to take down. If it's a like for like the rest should be easy.

1/4 inch luan plywood to protect the roof.

 

[CharlesinGA]

There are several good Youtube videos that show how to get an A/C unit on an RV roof.

 

[workinonit]

1/4 inch luan plywood to protect the roof.

Good idea. Just a thought. The one I installed (Coleman), had a pinch gasket that basically torqued to a built in spec so there are no additional sealants needed. I had to remove my Wineguard 360 as it was in the way so I had to use some Alpha self leveling but for just the AC there should be no sealant needed.

 

[whiteva]

The gang has pretty much covered each step in enough detail for you and friends to accomplish the swap out. The first thing is to keep the beer locked up until AFTER the project is finished.

My "faux pas" should be a warning to others!

 

[Gary RV_Wizard]

The rear AC unit does have a heat pump function which I'm reading that basically it's the same as units w/o that function but with some added features that allow it to be used for heat in moderately cool temps.

The physical heat pump unit is much the same but the control wiring wiring is more complicated. The thermostat has to be able to select heat vs cooling and some units also have a tie to the furnace controls so the furnace can kick in if it's too cold for the heat pump. And heat pumps more often have two-speed fans to manage. Again, not a big deal if the new one is an exact copy of what you already have, but if you got one with an extra feature or two, I guarantee you will be scratching your head.

It seems to me getting the exact same model AC, as you mention, would be the only way to go.

Of course, but the very first challenge may well be finding that exact unit. Yours is now 14 yo and the identical unit may no longer be in production or simply not in stock anywhere. Then the brand maker will probably say something like "Model xxxx-yz is now the replacement for that" and the fun begins...