Loose Roof Air

[CAPT MOGUL & Sandy]

I ran into a situation a ways back dealing with the roof airs. On the pre purchase quiz with the RV dealer service mgr. One of the questions I asked was about the roof condition and if the roof units had been inspected. His answer is typical, of course they had been inspected and were resealed ( He He ). On our second trip water on the bed and rear drawer top area, didnt rain on the first trip. Had the dealer reseal rear roof unit. Several months ago,while doing some service work at my brothers shop in GA. Sandra was busy cleaning up after me and asked to wash the A/C filters. For some reason I decided to take a flashlight and inspect the condenser and what I found sent chills up my spine. The front A/C uses 4-3/8x4 bolts to secure it to the bus ceiling framework. 2 were completely un screwed and laying on a screen and the other two were on the verge on dropping out also. Upon checking No2 A/C I found a simular situation with one out, one snug and two were at their end of threads. No# 3 was tight as I guess they really did what they said they were going to do. I respectfully suggest others with roof A/C do a flashlight check. Ed

[Ray Davis]

Ed,

Thanks for the suggestion. I will be picking up a coach with roof air in two weeks and I wouldn't have thought of that.

Great idea!

Ray

[dreadnought]

I almost lost the roof air off my bus trailer in Arizona last month. Went in the trailer & looked up, saw daylight. Went to a truck stop, pulled up beside a concrete lamp post pillar, put my 3 step ladder on top of it & crawled on the trailer roof. 3 of the 4 bolts that hold the AC on were broken and the 4th was bent like a pretzel. The AC had rotated 90 degrees. The duct from the unit to the fascia panel below was destroyed. No way to fix it on the road so I hooked a strap to it & eased it over the trailer edge & down to my wife below. They weigh about 75#'s so it was hairy! Morals of the story are:

a. look at the bolts holding your AC's on. Mine were like 3/16" diameter! Way too small.

b. pray you never have to get a roof air off the top of your bus on the road. The only way to do it would be throw it.

c. Get Cruise Airs. Then you can worry about getting TO the AC's to work on 'em.

[merle&louise]

Bill,

I have never been a fan of roof AC (please pardon the pun). I like basement ACs - cruise airs, etc. My coach has 2 basement ACs built by Specific Climate Systems in Ft. Worth, TX. The evaporator, condenser and compressors are in one neat unit which is located in one of the bays. The entire assembly is in a box and can be removed and UPS'ed to the manufacturer for overhaul or can be repaired at the site. It has 2 compressors; on the low setting it will run on 30 amps using 1 compressor and with 50 amps it uses both compressors. Really a nice system.

Specific Climate Systems 817 293-5313

[Joe Cannarozzi]

For those with roof air. The first thing I would say is remember EVERYTHING we do on these buses is a compromise. I think roof air is a reasonable one for a whole number of reasons.

With that said here is what it is. I have much experience with these. That gasket is around 1 1/2 by 1 1/2 by 14 inches square. It is like a stiff sponge material, it is porous and that is bad. Additionally after initial instalation the weight of the unit compresses it even more with time and that is also bad. They do not suggest any sealer of any type and that is bad.

On previous campers with roof air I took a piece of either stay-put mud flap or conveyor belt either one and cut it to duplicate the old gasket, in place of it. Secure it to the roof with good silicone and let dry. Then apply plumbers putty to the top of the new gasket you have made to give that a good seal to that roof unit and also allow for future removal of the roof A/C.

That flange that is formed by the mud flap permanently attached to the roof foums a dike it is not porous and does not compress.

One more thing, Jam nuts on the threaded rods where they thread into the bottom of the unit and finish off with lock nuts.

IMHO if you continue to work with the factory gasket you are gonna have problems.

One other way to prevent leaks, any leaks, is to simply park leaning all the time:rolleyes:

Seriously if out and experiencing a leak rolling the bus to one side or the other will often quickly remedy the situation until you nail it down.

[Just Plain Jeff]

First of all, last winter I was accused of spending too much time on the roof of our camper right here on this forum.

Well, hah-hah to my critics. What happens there happens on the inside.

According to most 'RV' warrantees, the owner is responsible for scraping and replacing all caulking and sealants on any roof penetrations every two years, otherwise warrantees are voided. Same deal on a Prevost, whether you have roof airs or not. Remember to completely remove any vestiges of the old caulking and sealant before putting on new sealant. It is highly recommended that you use self-leveling sealant, not silicone. If you do it on at least a warm day, it will get into all the little greeble places that silicone doesn't; easier to remove the next time around.

No matter where you live or how the camper is stored, the caulking/sealant on any roof penetrations will deteriorate and will ultimately cause water leakage. On a Prevost, you have to be very careful up on d'roof due to the thin layer of metal between the bracing...walk only on the braces. If you use a conventional ladder, make sure to wrap it careful so as not to damage paint or awnings.

Unlike many here, I like roof airs. We had four of them on our Vogue as well as OTR, and it was a great combination. It put the cool air flowing down from the top, very efficient and did NOT rumble or produce any unwanted noise. If the coach had been sitting and was hot, it could be cooled down in a very short period of time. If there is a problem with a roof air, just about any RV joint can help you out here with replacement. You can also get roof airs with heat pumps, so they can do double-duty if you choose on those chilly evenings or mornings. Of course, with four units, it looks like tract housing up top, but if you drive fast enough, most people will be so terrified of what is coming, they won't notice.

Part of getting up top of the camper is to inspect the condition of vents, antenna, awning brackets, SAT dishes, air conditioners and whatever else you may have up there. It is just as important as having a clean engine compartment or any other maintenance issue.

For XL coaches, it is also a good time to check on the clear coat over the paint, which has a tendency to deteriorate over time and start to flake off. This also need immediate attention as it doesn't get better by ignoring it.

If you can't get up on the roof yourself for health or other reasons, send your wife. At least she'll vacuum it off and start asking a whole bunch of questions about the stuff up there. Then you can lean back and mumble a bunch of ramble and she'll think that you are really smart.

Roof people are good people.

[Ray Davis]

So, this might be a dumb question.

So, the coach I'm purchasing has roof airs. But, I believe they are all ducted, meaning that the bottom half of the A/C isn't visible (I guess, I've only seen pictures at this point!).

So, are their usually access doors to get to the underside of the unit? To check the bolts mentioned above in this thread, don't you have to get to the A/C unit from the bottom?

Thanks,
Ray

[tdelorme]

So, this might be a dumb question.

So, the coach I'm purchasing has roof airs. But, I believe they are all ducted, meaning that the bottom half of the A/C isn't visible (I guess, I've only seen pictures at this point!).

So, are their usually access doors to get to the underside of the unit? To check the bolts mentioned above in this thread, don't you have to get to the A/C unit from the bottom?

Thanks,
Ray

Ray, the units will be ducted, but one of the air outlets will be right at the underside of the unit. Access to the filter as well as the attaching bolts will be through each of these "main" outlets. Our SOB plastic coach has this set up and while much better than the old roof air deal, they still make enough noise to be annoying IMHO. Could well be that the roof airs on the Prevost you are looking at have better performance than what I have on the Country Coach Intrigue. Mine work great and keep the coach nice and cool but man the noise is a pain in the arse.

[Ray Davis]

..... but man the noise is a pain in the arse.

I guess I'll find this out in a couple of weeks! :)


ray

[CAPT MOGUL & Sandy]

I am sure each converter will address the roof air in their own way but our Royale after you remove the filters you can see the condenser. Each to his own but I only looked for a machine with roof airs. Simple, cheap to repair/replace and since I use ear plugs at night I dont hear a thing!!!!! Ed

[rmboies]

One thing I haven't seen addressed regarding roof airs is the drain for each unit. I only know about this because this past summer I helped Bob while he attempted to unclog them. Water would not do it, we had to use an air compressor and power pressure the dirt and debris through the lines. It worked, and all is well for now.

Regarding the noise issue of roof airs, at first that bothered me as well. However, after reading the manual, ahem, we discovered that we were not using the automatic temperature and fan controls appropriately. The noise is not annoying now and the coach really stays cool.

Something else worth noting. We have four roof airs. Brian, the service manager at Millennium advised us to run one even number air and one odd at the same time. According to him, this puts an equal load on the invertors. As far as traveling down the road, we have found that running the driver air only works well for us, no need to even use the roof airs so far. Personally, we have had both cruise air and now roof air and the roof air seems much more efficient.

[win42]

A product I would reccomend for sealing between your roof and your AC Unit or roof fan is Butyl Tape. As wide and thick size as you can get to fit the flange area. Roof and bottom of the flange must be clean before putting tape down. Hide the tape under the flange from sun if you can.
cut matching z shapes at the corners so thickness does not overlap.
Always use nylon inserted lock nuts on the bolts. 5/16" min bolt diameter.
The material stays soft in weather extremes. Good Luck.

http://www.atlasfasteners.com/butyl.htm

[CAPT MOGUL & Sandy]

I just read Ed's comment about wearing ear pluggs at night. I guess he just told on me HUH? Sandy