740 (1987-non turbo) - A/C electric condenser fan

Peter Coutts · Post by **Peter Coutts** » 02 May 2006, 07:36

My A/C works but just does not kick out enough cool air. It has been serviced and some parts are relatively new such as the compressor.

I previously removed the seized a/c electric condenser fan that sits in front of the condenser rad. The garage is telling me that I need to replace the fan and then I will get colder air.

I live in a cool enivironment in Canada and have read articles that the fan only turns on in high temperature zones such as south US when the water temps get really high in the engine radiator.

Does anyone really know if this fan is actually needed and if it would indeed improve my cooling. If not needed, then what else should I look to to squeeze a few more degress of cool air.

Peter

LaRy · Post by **LaRy** » 05 May 2006, 08:39

I would say that you will not get any more cold air from the system by a fan. You can use the air-condition as long as the car is moving and if you stop, you should switch it off within one minute. The fact is that the return from the condenser should be rather cool. If you close your hand around some connection at the return from the condenser, it should not be warmer than you can keep on holding it. The return pipe is the smaller one of the two pipes going to the condensor. If the return is not cold, the pressure will increase to an unalowed level in the coolant. The over pressure sensor will stop the compressor, but it is not good for the system to use this function continously.
If the origin fan is to expensive, you can buy one of those extra cooling fans you use if you have a caravan. Install the thermostate sensor bulb closely connected to the return pipe from the condenser, use a pipe clamp and some insulation around so you really get the temperature from the return coolant. Make it start at rather low temperature, you will soon find out a good value that makes the fan start if you are at a stop-ligth, but switch it off when the car starts moving.

petershen1984 · Post by **petershen1984** » 05 May 2006, 09:42

Ditto that. My cooler fan runs intermittently, but when it's not running, while driving the compressor spins faster and the engine's mechanical fan pulls enough air to also turn the defunct fan.

If the compressor doesn't have enough refrigerant to compress, then you will also get intermittent operation. You should check for leaks in the system.

Peter Coutts · Post by **Peter Coutts** » 05 May 2006, 09:43

Thanks LaRay:

I have given up on the fan...definiately not needed in our climate...never comes on and the reason the garages have so many seived units not working.

The compressor is not cycling which makes me think that I have a relay problem or need to recharge the system or the compressor is shot. Compressor is only 2 years old so lets just hope it is only a recharge issue.

Any idea where the relay is located for the compressor?

Peter