Automotive Air Conditioning Information Forum

I have a 59 Deville I can't get ac to work. It has a new compressor from caddy daddy, the hot gas valve was sent off to Florida and completely restored and a new unequaled expansion valve. Upon opening the system nitrogen was blown through all components and hoses. Only the evaporator and condenser are not new. Leak tested with nitro and vacuumed over 24 hours. Charged with 134 but plan was to swap out with hotshot 414b or mp66 once it started working . The low side pressure won't go below 75/80 and temperature clamps show return line to compressor much hotter than discharge. We even swapped out the a6 compressor a 2nd time thinking it had to be bad. Hot gas valve tech started all valves are tested prior to shipping back. Could these conditions be caused by condenser or evap some how ?? Any help would be greatly appreciated.

The A5 with the Hot gas bypass worked well. The valve is an easy rebuild, sometimes the cam & pintle are worn.

An A6 conversion probably works ok, never messed with one.

Are you usure of the hose routing? Pics in this thread:

https://www.autoacforum.com/viewtopic.php?f=3&t=331

Finally how much Oil in the compressor? What type? How much 134a in the system?

I can't see why you would switch to mickey mouse gas if you can make it work on 134a. I would have stayed with R12.

It's only charged with 134 till we get it working and for recovery purposes. The ac machine isn't set up to recover mp66 or hotshot,or r12. But like I said the r134 makes it a lot easier to remove while verifying operation of components. Hoses in and out of hot gas valve appeared to be different size connections but it does seem like that (hoses crossed), I'll double check though. What are your thoughts on the A6 compressor, I don't believe it to be a match with the stock OEM compressor from what I'm now finding out .

Again.

What type of oil, how much, and where was it installed?

How much 134a was charged in to the system?