In Reply to: Clutch fan affects performance of the A/c posted by Anil on February 21, 2000 at 08:44:33:
I have a '90 520i.The aux fan works based on 2 inputs ie form the a/c and the other from the temp of the radiator.If the a/c is switched on,the aux fan runs at a slow speed and if the engine temp heats up,the aux fan runs at a high speed.
This is how the system is designed.There is a temp switch at the rh side of the radiator that sends the signal to run the aux fan whenever the engine heats up more than usual.
The a/c in my car doesn't provide sufficient cooling when the car is at idle but cools great when cruising.This is due to the slow turn of the aux fan.Unlike the MB where the fan speed is high and it employs the 12 blade fan,the cooling of the condenser is optimum,thus a/c is cold.
moots '90 520i
: The technician at the Air Conditioning place told me that because I have a weak clutch fan i'm not getting the full effect of the A/C. My clutch fan is due to change.
: Also, when the A/C is on the Auxilary fan spins at a low speed. When the engine temp increases beyond a predetermined point, the fan spins faster. Is this good.
: My father's MB however, when you turn on the A/C, the Aux. fan spins at a very high speed and its a 12 blade fan so it makes noise like hell. Now the A/C in that car is great.