In-dash air conditioner - Worth converting or fixing?

We do not use the dash AC we run the generator and the roof AC. Pull the curtains on the overhead and on HOT days close off the back end of the RV. We have a fan right behind the front seats to blow the air into the cab and have always been cool. We like it this way since it takes a huge heat load off of the engine and the back end is cool whenever we stop. Also when the boy is with us we would have to run the house AC for him so why run both.

j-d : I have the "dealer" York compressor, not the factory cylindrical. I pushed the Schrader on the fill side and I get nothing. Seems like its totally empty.

The in-dash A/C is 20K BTU? Wow ......

Ok, then. It sounds like I should get hold of a vacuum pump and see if my R12 system holds vacuum. If so, then I will hot-wire the clutch so I can confirm it is working. If that is a go, then I will have my buddy (HVAC dude) get me some R12 and we will re-charge.

Thanks for the feedback folks. Will update this thread as I make progress.

Jose

Good point, paul. He'd have to get somebody with a license to evac and charge it, but the periperals to convert aren't cheap. There's a ton of R12 out there, and meanwhile the price of 134 has climbed. Diff might not be too bad. Just do something before the other shoe falls. R134A is "now" considered harmful. Gee wow. R12 banned then R22 was accused but never convicted. Banned anyway.

I'd consider repairing it and recharging with R12. It should cool the cab fine, but asking it to cool the house is asking too much.

Which system do you have, Jose - The "factory" with a cylindrical compressor or the "dealer" with one that looks like a mower engine?

We had "dealer" and though it was a pain in several ways, it blew COLD after conversion and I would not have wanted to do without it. Our Holiday on 83 E350 was 24-ft but we never ran roof air on the road. Only the dash and it cooled the whole rig. Vehicle A/C is rated in the 20,000 range and your rooftop is probably 13,500. Whenever we try to run roof air for travel, it just doesn't satisfy. You want the air in your face, not behind your back.

You need new oil, the 134 of course, new drier, fittings and label, plus a HPCO switch (High Pressure Cut Off). No need to replace hoses or O-rings unless they're failing. If it's factory, new orifice tube and new LPCO switch (or adjust the old one). If dealer, new expansion valve.

Either way don't overcharge. Start at 60% of OEM R12 charge and see what it does. Your low side may wind up low, but if you try to raise it you may find the high side goes too high. Conversions tend to jump into excess high side pressure.

Kind of a tough call. Its true that the dash air won't cool the entire coach but it makes a difference esp in the front 8-10 feet when driving. Not to mention the comfort level of the driver and front seat passenger. On really hot driving days you'll want(need?) both cab and overhead air to stay cool.

Personally I'd want the cab air to work but it all comes down to how much you want to spend.

Another thing to consider is how much you'll be driving versus sitting. If you take short trips or not many trips, maybe you can sweat it out with no cab air.

If you take longer or many trips, also consider that the extra fuel you use to run the generator (maybe 1/2 gallon per hour) may add up over time to more than the cost of the cab AC switch?