Another AC thread..

nealf2002 · 05-21-2009, 07:39 AM

I have searched the archives and examined my car and read the owners manual, for my '82 SC RoW, for the correct way to attempt to use my AC or at least to get the fan blowing. My fan for the heater and defroster works when I slide the upper lever to the right. I know that much. When I turn the two knobs in the center console all the way to the right there is nothing happening. I have a bunch of questions:

Are there two different fans in the car, one for A/C and one for heat/defrost?

What position should the three levers at the top be in to run the AC? Or does that not matter?

I did a brief check of the fuse box and checked the snugness of the relays but did not get anything to happen.

I do not get ANY air from the center vents...Why???

Can you all help me and maybe give me some areas to start testing things?

Thanks.

Neal F

JMH82SC · 05-21-2009, 08:03 AM

The heater / defrost levers do not effect A/C. The center vents for the A/C are controlled by the fan switch in your lower center console. The fan for the center vents is in the luggage compartment next to the brake master cylinder.

nealf2002 · 05-21-2009, 08:05 AM

So, you are saying there are two different fans?

Thanks again.

JMH82SC · 05-21-2009, 08:32 AM

Yes, the fan for the center vents is totally separate and on my 82SC it is on the same fuse as the condenser fan so runs at the same time. The condenser fan is in the black box in front of the gas tank and spare tire.

JFairman · 05-21-2009, 09:17 AM

Correct terminology would help here.
The only AC condenser fan on any 911 before 1990 is the tiny thing thats is usually burnt out by now way up in the nose of the car next to the battery and it takes air from behind the front bumper and blows a very tiny amount of air downward over the small front condenser.

The evaporator fan is in the "smuggler box" which is under the door just behind the gas tank. That compartment was origonally put there for a rare gasoline heater that was mostly a northern european option way back in the early sixties.
The evaporator fan is the one that blows air out the AC ducts and there is a silver colored bosch relay that turns it and the compressor on, screwed to the passenger side of the smugglers box.

The frontmost relay on the front trunk fuse and relay console turns on the small condenser fan in the nose of the car.

If you get no air from the center vent it may be a fuse, the relay in the smuggler box, or the evaporator fan is burnt out or seized. If it's only seized you may be able to free it and oil the motor to get it working again but you have to take apart the black plastic evaporator box in the smuggler box to get at it.

GH85Carrera · GH85Carrera's Garage

One other fan that is totaly seperate is the heater. What other can can have the A/C, the fresh air and the heater on all at once?

JFairman · 05-21-2009, 09:22 AM

Quote:

Originally Posted by nealf2002

So, you are saying there are two different fans?

Thanks again.

Yes.
The defroster, heat, and AC fans are all seperate.
The HVAC system in a 911 is an afterthought... and pretty much a joke.

CBRacerX · CBRacerX's Garage

If everything is working perfectly, the 911 AC is "OK" and is improved with more airflow (hence the 87-89 larger vents.