Any E30 A/C experts out there?

[Paul DeZan <dezan@xxxxxxxxxxx>]

I have a bizarre intermittent A/C problem on my '88 325is...Dinan
Engineering has told me to replace the dryer and the expansion valve,
but I'm looking for a second opinion.

Symptoms

1) When the A/C compressor button is depressed, cold air may or may not
start blowing (usually it does).

2) After a short time (anywhere from 30 seconds to five minutes), cold
air will stop blowing (that is, the fan keeps running but the air gets
warm and humid).

3) Turning off the compressor for five or ten minutes, then switching
back on will often provide cold air for another few minutes.

4) If the recirculation button is pressed while the system is blowing
cold air, it will often extend the time the air remains cold - sometimes
for hours.

System is fully charged - no leaks. When it's working, the system blows
ice cold air.

Any thoughts?

Thanks...pld

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