[Rod]

sounds like they tried to tap 12 volt off ign switch 12 volt feed to ddec. yellow wire. would suggest to tap off 12 volt feed in front box below drivers window toward rear. breaker should be extra open only live when ign switch is turned on. There are two bus bar feeds there one 12 volt and othe 24 volt 12 volt is toward rear and is verticle stack. yellow=12 volt red is 24volt always check Bob

[Bob]

Thanks,

Will follow your suggestions and see if that works.

[Alvie]

In that 12 volt stack there are several breakers with wires on them that lead to unused accesories that are dead end.. If you see one that your coach is not equipped with feel free to use it. Is common practice to pre wire these coaches for every possible option then use only what the customer orders…FWIW

[Bob]

You have been a great help. I am installing tow roof airs/ heat pumps as the coach air finally gave out. now ttrying to decide if I should pull the thing and have another bay, or go thru the expense ov converting to new gas for the unit.

[Rick & Denise]

The worst thing that can happen to a full coach over the road system is th ecompressor can puke. But the compressor replacement is likely to cost no more than what it takes to put two roof units on the coach. There is a lot more than just buying them because you have the issue of penetrating the roof, assuring they are sealed and leak free, running wiring, possibly changing the ceiling to duct them, and then you still have so much less cooling you aren’t ever going to be comfortable driving into the sun on a summer day.

But you comments raise some questions. OTR air conditioning is only for when driving. How are you currently cooling the coach. I see owners of older coaches tend to think replacing whatever systems the coach has with new as somehow being better than fixing what was there originally. Usually abandoning the original equipment and installing new is creating a different set of problems, if not immediately certainly in the future. But why are roof units a substitute for OTR? If you abandon the OTR you have no driver’s air so by the time you replace the big OTR with a smaller compressor for driver’s air, plus add roof units you likely have as much money and effort involved, and far less capability.

On an 87 coach I suspect you will either have to have the generator running or you need a couple of good sized inverters and a bank of batteries to run the roof airs. Just trying to understand the logic. It would help if you added some information about the coach in the signature line. Maybe that will help us give better opinions.

[AL]

Start one! Glens in Texas just went thru this. I think he would respond with his experience if you get his attention and results.. Straight roof air without ducting etc is very noisey in my opinion.. The major problem with your present system is prob dirt you can’t see in condensors and evaporators.. might need some major TLC (cleaning) then be good for a very long time. Just my take.