A/C system pressure

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Jul 16, 2014 | 02:46 PM

caryb78

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Racer

Joined: Jan 2013

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A/C system pressure

Can someone tell me the high and low side operating pressure for a fully charged A/C system on a 78 pace car- L-82.

Jul 16, 2014 | 07:12 PM

DUB

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From: Charlotte NC

Not a simple question to answer. Temperature and air moving across the condenser make a difference in gauge readings.

If you are planning on working on this when you do not know what you are doing...do yourself a favor and take it to someone who knows.

It is NOT as simple as putting more freon in it. Putting too much freon in if it is being changed will possible make it not work correctly.

DUB

Jul 17, 2014 | 03:22 PM

caryb78

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Racer

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Thanks

Quote:

Originally Posted by DUB

For your concern. I do know what I am doing but I cannot access my service manual for the temp/press chart. Generally speaking the pressure at 75degreesF is a good avg.

Jul 17, 2014 | 03:28 PM

MelWff

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does this article help, has pressures at higher temp

http://tech.corvettecentral.com/2008...4-ac-retrofit/

Jul 17, 2014 | 05:39 PM

hugie82

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Joined: Mar 2007

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From: Bridgewater nj

A very simple answer is on an 80 degree day. With the compressor on you want to see around @40 psi on the low side. With the compressor off it should jump up to @80-90psi.

Jul 17, 2014 | 05:43 PM

DUB

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From: Charlotte NC

Quote:

Originally Posted by caryb78

For your concern. I do know what I am doing but I cannot access my service manual for the temp/press chart. Generally speaking the pressure at 75degreesF is a good avg.

No worries. I ,obviously did not know that you know what you are doing. 'Some' people attempt to do this without proper knowledge and can get hurt or damage things...so I was erring on the side of caution.

DUB