Hi,
the A/C compressor on my 90 RRC decided that it was no longer going to pump freon, and just sit there like a lump. I've determined that there are no leaks in the system, and the proper amount of r-12 is (was) in it.

Since I have the system open, and will be replacing the compressor and receiver/dryer, I'm going to switch to r-134. To do this, it's recommended to pull the expansion valve (ugh!) and flush the lines. My Q, while I have the dash apart, is it advisable to replace the A/C thermostat? How often do they fail? It's $97, so it would put my total for A/C repairs at $420, not including freon.

Also, has anyone used the replacement resistor packs from Altantic British? Are they better than the stock ones?

Not that I have an answer to this question but more of an additional question.

My AC has decided to not work this year. Not work as in the compressor clutch does not engage. I'm not getting power to the compressor. The fuses are ok, the "temp" (dash) switch is working, I've tried jumping the coolant temp switch (at the thermostat housing) and I've tried moving around the relays...

Any other ideas?
Thanks!

My AC has decided to not work this year. Not work as in the compressor clutch does not engage. I'm not getting power to the compressor.

Have you checked for power on both sides of the high pressure switch?

Pete

There are a lot better replacements out there than R-134a, that do not require flushing, etc. Do a google for 'r12 replacement'

There are a lot better replacements out there than R-134a, that do not require flushing, etc. Do a google for 'r12 replacement'

Yeah, I've seen FR12 and other 'replacements' available out there. I talked to a friend in the HVAC business, and a few guys at NAPA who've been through the automotive A/C courses. All of them recommend the r-134a conversion over the substitutes. Most of it was for warranty of parts and serviceability of the system by others.

I''ve decided to replace the thermostat, i'll do an autopsy of it afterward, see what's inside of it.

Yeah, I've seen FR12 and other 'replacements' available out there. I talked to a friend in the HVAC business, and a few guys at NAPA who've been through the automotive A/C courses. All of them recommend the r-134a conversion over the substitutes. Most of it was for warranty of parts and serviceability of the system by others.

Yeah, the 'second generation' R-12 substitutes have not been approved for warranty on compressors (just like the first generation R-134a was not initially).

That said, they perform better than 134a, and are being recommended more and more by mechanics. The ones I talked to recommended not converting R-12 to R-134a, since there can be such a significant performance drop. I also like that the second generation substitutes don't require the care that R-134a does (complete cleanout of the system, drier, etc)

YMMV