Another AC Question

[Yan2947]

I hope this is an easy question regarding my 89 911 front condenser (blower)fan. When I turn on my interior fan switch for my ac the fan switch powers the AC temp switch causing my compressor to kick on and the compressor stays on unless the temp probe in the evaporator tell the temp switch to turn off the compressor.

1. what causes my front condenser fan to turn on? Is it the interior fan switch for the ac - is there a lead that powers the condenser fan? or is there a pressure switch that eventually turns on the fan above the condenser?

thanks in advance!

Yan

[RSTarga]

the fan is the ON switch for the a/c.

[sacoffee]

If your AC fan is on the front blower is on full time

[Yan2947]

Thanks for the response.

[kuehl]

Originally Posted by Yan2947

I hope this is an easy question regarding my 89 911 front condenser (blower)fan. When I turn on my interior fan switch for my ac the fan switch powers the AC temp switch causing my compressor to kick on and the compressor stays on unless the temp probe in the evaporator tell the temp switch to turn off the compressor - CORRECT.

Originally Posted by Yan2947

1. what causes my front condenser fan to turn on? Is it the interior fan switch for the ac - is there a lead that powers the condenser fan? or is there a pressure switch that eventually turns on the fan above the condenser?
Yan

The stock system did not have a refrigerant pressure switch. If you added one it would only shut off the compressor clutch if pressures dropped or rose above its set points.

The front condenser fan is turned on an off by the thermostat, along with the compressor clutch, when the temperature of the evaporator coil is above (system on) or below (system off) it's set point. Power travels from the thermostat to the front condenser fan's relay terminal 86.

Below is a link to the earlier years ac schematic, which is much alike later years
http://www.pelicanparts.com/911/911_Parts/Electrical/911_electrical_82SC_AC.jpg

Call me if you need further help.

Griff

[Yan2947]

Thanks for the reposnses. I figured out that my inline fuse was blown. I got another one and plugged it in next to the front condenser blower fan. Turned on the ignition and put the AC Fan on. Once I did that I heard a freight train coming! I guess my blower motor may have some issues so I will take it out and inspect it.

[Yan2947]

I took apart my front AC Condenser blower that sounded like a freight train. I got it out of the plastic compartment but couldn't get the fan off of it. That little allen nut is really frozen on there. I ended up putting some needle oil on the shaft in different areas as per someone else's thread. (well I just had needle oil) That is all it needed. It is whisper quiet now