AC low & high side on an 88 924S

[solex3274]

I have done a bit of research on bringing my AC system back to life, but which port is the high side and the low side on a 1988 924S? One valve is located down by the compressor, the other next to the firewall. Porsche moved these ports around depending upon early or late 944.

My second question is regarding flushing the system. Do I need to flush each individual component of the AC system before I install the new compressor? Can I simply hook up the flush and shop air to the compressor hoses and flush the entire system?

[mikepellegrini]

I was asking similar questions a couple weeks ago and got some good answers:
http://forums.pelicanparts.com/porsche-924-944-968-technical-forum/672927-what-look-vacuum-pump-c.html

It's not good to use shop air to pressure test or flush the system because of the moisture in it. What I found is that unless there's been a catastrophic failure (the compressor blew up) it's not usually necessary to flush.

The low port on your car is located kinda on the top of the compressor. To get at it, you really need a 90 degree elbow fitting like this: https://www.ackits.com/pc/35-50003/conversionitems/35-50003+-+Low+Side+Conversion+Fitting+%2890+Degree%29

[John_AZ]

Originally Posted by solex3274

I have done a bit of research on bringing my AC system back to life, but which port is the high side and the low side on a 1988 924S? One valve is located down by the compressor, the other next to the firewall. Porsche moved these ports around depending upon early or late 944.

My second question is regarding flushing the system. Do I need to flush each individual component of the AC system before I install the new compressor? Can I simply hook up the flush and shop air to the compressor hoses and flush the entire system?

The high side on the '88 924S is located next to the receiver drier in the headlight well.
The low side on the '88 924S is located against the firewall.

Mike is familiar with the early 944s and then he would be correct.

If you are replacing the leaking compressor that did not produce "black death" or burned out coil you could get by with just an additional receiver drier and a condenser flush.

GL
John

[solex3274]

Thank You Gentlemen for the information. This will be my first experience dealing with air conditioning, and by doing the job myself at a reasonable cost gives me satisfaction.

In addition thank you for all the previous posts and replies that I was able to research on this topic.

[mikepellegrini]

My mistake! No, I don't know 924's.

[alfadoc]

Something I posted last summer:
"If you look in the factory service manual and the factory parts drawings, they show for 85.5 up as low side by the fender, and high side by the dryer. However, there is a notation in the FSM that the configuration is changed for 87-up, to high side by the fender, low side on the compressor. The low pressure switch is in basically the same location on both.

Some of you may remember me posting a while back that I couldn't get my A/C to charge correctly. Among other problems, I wasn't looking at the lines, rather I was taking the drawings for gospel. Skinny lines are high side, fat lines are low side. I had been trying to charge my car through the high side. Doh!"

Hope that helps!