Vacuum on the low side

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HendrixTX
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Joined: Fri Aug 11, 2017 4:11 pm

Vacuum on the low side

Post by HendrixTX »

Hi all,
I'm trying to recharge a 134a converted system that had the condenser, drier, evaporator and expansion valve replaced. Pulled vacuum on the system for 90 mins then let it sit for a few hours and confirmed the vacuum held. I've put 4 12oz cans of plain SUVA in and I'm getting 150psi on the high side and vacuum (-20) on the low. The spec fill for R12 is 39oz, and I was expecting to put in ~30oz of R124a. Since I'm up to ~48oz of R124a, I'm afraid to put more in. The system is holding pressure (92psi low / 115psi high right now.. still equalizing). What do you think? Should I keep putting in more refrigerant?!
Thanks much for your help!
Chris

Car is a 1986 Porsche 911
HendrixTX
Posts: 2
Joined: Fri Aug 11, 2017 4:11 pm

Re: Vacuum on the low side

Post by HendrixTX »

Oops.. sorry for the fat fingered typing.. R134a (not R124) ;)
Temps were ~90F when filling.
Thanks!
Dougflas
Posts: 379
Joined: Mon Apr 18, 2016 6:10 pm

Re: Vacuum on the low side

Post by Dougflas »

Low side shrader not opening. Make and model of vehicle?
Diametric
Posts: 9
Joined: Mon Aug 07, 2017 3:13 pm

Re: Vacuum on the low side

Post by Diametric »

You sure it calls for that much freon?

A Dodge caravan with Rear AC uses about that amount...maybe a bit less. Seems like a lot for that car. But refer to the FSM.

It's rear engine so maybe a lot of plumbing to get from the dash back to the engine and back again?
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