what refrigerant for '77 A/C?

maznblu · 07-07-2003, 08:37 AM

Greetings.
We just returned from a three week trip through the steamy upper midwest (Wisconsin, Minnesota, Iowa). We had to rely on a couple of fans to cool ourselves down in the 90+ degree heat as the A/C didn't work. I suspect that it needs refrigerant. I don't have the manual here, so can't quote the make and other specs. My basic question, however, is what refrigerant to use? With regulations about CFCs, is there a way to convert an older A/C unit to modern refrigerant? Or am I looking at investing in a new A/C? Everthing else seems to work fine (switches, blower, etc.).
TIA for advice.
Eugenie

thenewkid64 · 07-07-2003, 09:18 AM

If you have an original Armstrong AC unit there are service ports. This would allow you to have a competent AC repair guy recharge the unit. It should use R12.

Parts are available to repair it, but there is not a conversion kit that I am aware of.

Chas · 07-07-2003, 10:21 AM

First off I wouldn't suspect low refrigerant as being your problem. I would check to be sure the condenser fan is operating and verify that the compressor is running, then check the temp differentials and see how much it is cooling. I would say that the refrigerant circuit is very well sealed and not particularly prone to leakage.

Chas

smily · 07-07-2003, 06:57 PM

My 1979 Armstrong has R-22

I bought a 30 lb bottle for 79 dollars and was told that I probably could not buy a 1 lb can.

Chas · 07-07-2003, 07:23 PM

Really, R-22?

I figured they all had R-12 in them.

Well, good news for all of us because last time I checked R-12 was running nearly a $1,000 a keg (30 lbs.)

What's that, like $30 some dollars a pound?

Chas

thenewkid64 · 07-07-2003, 07:51 PM

Uhhhhh..........

I may have the numbers mixed up. I have been discussing Automotive AC this week on the Motorhome. That would explain why I have R-12 on the brain

Chas you have the price right, that is what the r-12 recharge is going to run, 30.00 / LB, 3 lbs min.

Well it's just money, I am fortunate to be young enough to make more, right?

MECHANIC · 07-07-2003, 08:23 PM

Quote:

Originally posted by EAP
Greetings.
We just returned from a three week trip through the steamy upper midwest (Wisconsin, Minnesota, Iowa). We had to rely on a couple of fans to cool ourselves down in the 90+ degree heat as the A/C didn't work. I suspect that it needs refrigerant. I don't have the manual here, so can't quote the make and other specs. My basic question, however, is what refrigerant to use? With regulations about CFCs, is there a way to convert an older A/C unit to modern refrigerant? Or am I looking at investing in a new A/C? Everthing else seems to work fine (switches, blower, etc.).
TIA for advice.
Eugenie

MECHANIC · 07-07-2003, 08:27 PM

My service manual says armstrong unit requires R-22