Roof Air Only

[flyu2there]

While preparing my top for a coat of tape coat, I removed the three covers for the roof air units. Mine were attached to the units by four sheet metal screws, two on the rear sides and two on the front of each housing.

Here is what I found. Of the twelve drilled holes in the covers, 9 of them showed stress cracks and three of them failed (broke apart) when I removed the screws, obviously the work of over torque and sun/heat. Whoever last worked on them (I admit, it wasn't me) put in larger pan heads screws as the fix for something that is obviously a weak link....the effect only delays the inevitable. For years I have seen these covers laying on the side of a number of highways throughout the land and my time was close by what I found. My fix was to re enforce all of the mounting holes with fiberglass and then to re drill the screw holes, followed by prep and paint.

Issue number two.......... Inside of these units you will find foam rubber strips which apparently serve as ducting for the condensor. All of my foam rubber was decayed and needed to be replaced (available at Loews).
A little contact cement did the job and the pattern is clearly visible inside of the covers.

Issue number three.......... The package unit itself was filthy inside and the condensor, although mine were all very operational, was at least partially plugged with dirt and debris. Compressed air and a couple of cans of coil cleaner did the job. I suspect that I had some loss of efficiency with all of the filth.

Admittedly these thing are a royal pain to get at, however I now believe that an annual inspection is a requirement. I will post some pictures soon on this one.

[HarborBus]

I had a similar issue with my AC shrouds. The middle shroud had bug chunks broken out where the screws used to go through and someone added three other screws elsewhere but those missing chunks allowed water to leak into the coach. I replace two of the shrouds with new ones that are guaranteed for 30 years (the AC units won't last that long). They can be purchased at:http://www.icondirect.com/ProductCart/pc/A-C-Shrouds-c3.htm. They don't have the foam on the underside though, I wonder how important it is?

[flyu2there]

I am thinking that the foam is very important for a couple of reasons. First, it provides support for the shroud to keep it from wobbling up and down hence putting wear and tear on the mounting screws and finally failure. Secondly, it appears to seal the condensor so air is drawn thru the condensor rather than above it. As mentioned, my seals were rotten, filled with dirt and just broke apart; I replaced them with 1/2 in foam pipe wrap (comes in six foot lengths), same dimension but far more impervious to dirt than the foam and the half inch center opening allows for needed flex, plus there is a heat treat in the mix of compounds. I also glassed all the area around the screw holes, including the lip. Finally I painted them in a matching tone to the bus, as original) acrylic enamel with hardner..SINGLE STAGE. :D

BTW you can cut a couple lengths of that wrap and place them around your wiper blades when stored, inside or out...it will keep them fresh and clean for a very long time.