Which direction is the correct air flow through the condenser? Red or blue?
I would say in the red direction, but the direction of rotation of the fan would confirm it, if it rotates clockwise looking from the condensor side, then the red arrow is correct. This all supposes that this sketch is accurate of course.
It's got to be the blue direction (you wouldn't want to restrict the hot exit side of a radiator with a reducing duct -- well, unless you're desperate). (No direct experience for me with the AC ducting on a 328, but) I think you should match the fan's airflow direction to the natural airflow direction caused by coachwork forward motion. If the fan blew in the blue direction would this dump the hot air into the front wheel well like a TR?
I would have to say Blue, because it sucks in air thru the RH side of the front grill and dumps it into the wheel well as 91tr thought. It would be unlikely to move in the other direction because it would have to dump air in a high pressure area and thru a restriction.
The correct answer is blue. It is a "pull" fan.....I know this as I just replaced one on my 1986 328GTS. The SPAL part number ends in an "A" which means "pull". If you do replace this fan, do know that the early model 328 fans are different than the later models.
That makes sense. Do you know what activates the sensor on the condenser? The one at the base of the blue arrow? Thanks
Heat/temperature -- the "sensor" is a thermal SPST switch. Its concave head is held against the straight part of the rigid tube exiting the AC condensor by the U-shaped spring clip. When the hot compressed refrigerant in this tube exceeds a certain temperature (which I can't recall now but it's hot), the switch closes, turning the condensor fan "on", so it's important that the sensor head have good physical contact with the tube.
