Air Conditioning

[Leroy Eckert]

Mine is the same configuration as yours Don. I do have a small leak somewhere that I cannot find. It leaks down about once per year but works great when it is charged. The leak must be very small. Converted to 134a.
Just curious, where is the expansion valve and evaporator in your coach?

Leroy Eckert
1990 WB-40 Smoke N Mirrors
Dahlonega.GA
Royale Conversion

Don Bradner wrote:

There've been a few A/C discussions in various threads recently - must be a calendar thing. I thought I would add my own.


I've always been very impressed with how well the overhead chassis air cooled driver and passenger in Blue Thunder. In previous SOBs on really hot days the dash air was never enough - had to run the generator and a house A/C as well. Blue Thunder is one of the 90s with the condenser back at the radiator rather than on top of the front cap.

10 days or so ago there was a big heatwave on the west coast, and I turned on the A/C for the first time in a couple of months - no cold at all, sigh. Ran the generator as needed to keep things decent, and waited until we got home to check things out.

On top of the hoses as they leave the compressor are R12-to-R134a elbow service ports. Both were loose, and a small amount of pressure on the high-side fitting caused it to separate. There was no gas escape, indicating that it was all long-since leaked out.

I assume that I am the culprit on this. I had to drop the pump in order to disconnect one of the gate valves
when I was searching for my chassis heater problems, and I'm guessing I hit the fittings at some point during the process. They are rather exposed and easy to collide with.

A local outfit did the service, replacing both fittings and using 7-1/4 lbs of R134a. An expensive lesson, for sure, over $600 bottom line.

The records from the coach's second owner shows a $700 bill in July of 2001 for "A/C repair" so I'm guessing that may have been the original conversion.

I know there are a number of folks who have posted that their dash air does not work, and they just use the generator/house air solution. We considered that, but even with the high cost of repair the economics appear to be in favor of the repair route. Our generator pulls about 1/2 gallon per hour when doing light work like a single air conditioner. At $5 per gallon that would mean $600 would run the A/C for 240 hours. At most that would be a couple of years for us, and probably less. We
will be traveling to the East Coast in August, and are likely to be in hot weather until we leave Florida in November.

I'll be sorry if it turns out that I have a leak somewhere else, but I'm fairly confident that I don't. The tech put plenty of fluorescent dye in with the refrigerant, and nothing has shown up anywhere.

Don Bradner
90 PT40 "Blue Thunder"
Eureka, CA