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Subject:Re: AC Service Prior to Pressure
From:Robert Fisher
Date:Fri, 13 May 2005 13:18:26 -0700

So I have three manuals in front of me, and I looked up another on the
internet just to be thorough, and no matter how many times I look at this I
can't wrap my brain around this statement:

"You have this all backwards Robert, which could lead to a guy blowing
his hands off, with shrapnel  when charging the AC system."

I wrote:

"The high pressure line goes from the front (in relationship to the van) of
the compressor toward the front of the van to the condenser- it returns
through the dryer to the expansion valve.
The low pressure line is a short piece that runs between the expansion valve
and the compressor thru the driver's side rear pillar."

Here's a quote from an automotive A/C service training manual:

"High side simply refers to the side of the system in which high pressure
exists. The high side is from the outlet (discharge) side of the compressor,
through the condenser, through the receiver/dryer and to the expansion
valve.

It is the compressor's job to create the high pressure (higher temperature)
so the refrigerant will be able to condense and release heat at the
condenser. A pressure differential is created at the expansion valve- the
dividing point of the system.

Low side is the term used for the portion of the air conditioning system in
which low pressure and temperature exist. From the expansion valve, through
the evaporator to the inlet side (suction) of the compressor, the
refrigerant is in a low-pressure state. This allows heat to be transferred
from inside the car to the 'colder' refrigerant, which then carries it
 away."

I was basically trying to give a simple illustration of the two sides of the
system so that somebody looking at it could figure it out without a diagram
or at least relate it properly to the incorrectly labeled Bentley diagram; I
don't see how I got anything backwards, never mind saying anything that
"could lead to a guy blowing his hands off, with shrapnel  when charging the
AC system."

Cya,

Robert

----- Original Message -----
From: "Robert Cardo" <rrecardo@WEBTV.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Friday, May 13, 2005 3:55 AM
Subject: Re: AC Service Prior to Pressure

> <<The high pressure line goes from the front (in relationship to the
> van) of the compressor toward the front of the van to the condenser- it
> returns through the dryer to the expansion valve.
> The low pressure line is a short piece that runs between the expansion
> valve and the compressor thru the driver's side rear pillar.>>
>
>
> You have this all backwards Robert, which could lead to a guy blowing
> his hands off, with shrapnel  when charging the AC system.
>
> The low pressure port is on the back of the compressor, the high
> pressure port is buried behind the rear pillar cover in later model
> Vanagon's.
>
> The bigger diameter line's are always the suction side, the smaller the
> pressure.
>
> RC