A/C Relay Question - 993

[e p slick]

Have fresh and functining A/C compressor + proper volume of refrigerant + lube oil. Also know that condensor fans are functionuing. Can only get 52 degrees at cockpit vent however (90 degrees ambient). Seems as if A/C relay may be cycling (if that makes any sense) since there is not a constant power feed to compressor spade connection. I believe that there are thermal switches in electrical system prior to relay so I would expect it to make sense to test them next.
QUESTION IS: where are they and how do I test them?

Appreciate any input since I am pretty lost at this stage.

EPS - Tucson

[axl911]

Hi Paul.

Glad to hear you got the 993.

Two things that could be doing it, high-lo pressure switch, evap core temp sensor.

Here is a link that got everything you need. What high/low pressures are you seeing at the compressor when it is running?

COMPLETE A/C Diagnosis - Rennlist Discussion Forums

[RSTarga]

38 degree difference is not bad. I don't believe these 36 degree reading at the vent, must be 70 outside.

[e p slick]

I am getting closer. 35lbs and 250lbs. Three way switch seems to be functioning properly. Rennlist discussion was of very siginificant help.

Thanks again

EP Slick - Tucson