Dead AC need recommendations

[Guest kool kitty]

My 1990 Reatta has been in the family sense new. The AC has not worked as long as I have had it. There is a dealer tag that dye was in the system but to my knowledge nothing was done.

The Reatta has 34,000 miles and is a nice car but it needs its AC back.

I took it in to have repaired as I already knew that the compressor front seal was leaking and that is the crux of my concerns.

I had assumed that R134a was to replace R12. But, I was told that there was no replacement for the Hi-Side Temp Switch to accommodate the higher pressure of R134a. As the switch in question was also leaking they tried to find a new OEM replacement. They found Napa or Car Quest part number 207645 which turned out to no longer be available. They suggested a good used part to replace it and install R12. I have no problem using R12 except for maybe the cost.

To people that have updated to R134a did they replace this switch and if not did it effect the usage in hot weather, etc?

[Guest Mc_Reatta]

Need to be careful about understanding exactly what part you really need. There are two temperature sensors - one on the low side and one on the high side. These are no longer available new.

There is also a low pressure cut-off switch near the low temperature sensor that stops the compressor from engaging if the system pressure is too low to safely operate the compressor. This is still available new and can be replaced even when the system is charged.

Neither of these sensors nor the switch needs to be changed if the system is switched over to R-134a or other refrigerant. Only need to replace if they are leaking or aren't operating properly. Temp sensors can be checked by using diagnostics mode.

Your better off sticking with R-12 if your having the work done and can afford the cost.

Here's a diagram showing the locations of these components:

A/C Sensor Locations - ReattaOwner.com

[padgett]

I have been changing R12 systems to R134a for over a decade. Modern compressors can handle either, just need to be sure to use the correct oil. No need to change any sensors.

By far, the most common failure is the compressor seals but regardless I'd flush the system and install a new compressor/dryer/oriface and replace any Orings in seperated joints.

[wws944]

Gmpartsdirect and gmpartsgiant show both the temp sensor (part #3526316) and the pressure switch (#1631399) as available new. Might try checking with them to see if they really are available.

Edited February 14, 2012 by wws944 (see edit history)

[Ronnie]

The Low Pressure Switch (Low Pressure Cut Out Switch) is listed in the Reatta Store on my website and is still available. I don't think the low or high temperature sensors are still available. I have one bad and have not been able to find a replacement.

[wws944]

Ronnie: According to the Illustrations pdf, the part number for 88-89 Reatta temp sensor is different than for '90+. The earlier part number is 1626146 and shows NLA at both gmpartsdirect and gmpartsgiant. So the obvious question is if 3526316 simply superceded 1626146 - therefore could be used in earlier Reattas, or if there is something that needs to be different. I have no idea what the answer is for your '88. But since the OP has a '90, the correct part seems to be available...