Any air-con techs out there??

[shortgq]

I've got a 1990 Ford Maverick> Now the air-con is nice and cold and still runs on the old gas. My question is in relation to the 4 wires which come out of the reciever/dryer. The relay for the elec air-con fan relies on two of these wires to earth the circuit therefore connecting batt straight to fan. Now this switch doesn't seem to be working as when i bypass these two wires and earth it the fan kicks in, i'm not game to unscrew switch because i will loose the gas i suspect. Does anyone know what might be the problem or how crucial is it that this electric fan works anyway.

Thanks

[murcod]

AFAIK the fan should run whenever your compressor is switched in.

[DAZZ]

This is na pressure switch, and unscrewing it will probably cause the refrigerant to be lost.
Two of these wires will be for the compressor circuit, when there is low or excessivly high pressure this will disengage the compressor clutch.
The other two wires will be for the thermo fan, this will come on when there is high system presure. (hot day, in traffic) This is not ideal in most cases. Having the fan on when the clutch is in is an improvement, and having the fan on continuasily when theA/C is on is better, especially off road.