Here is an A/C question for those in the know.

The setting: hot, humid New Orleans, LA heat; a/c condensor that is behind a fmic, and an a/c compressor that has a short squeak every time the a/c is turned on.

What it is doing: the a/c comes on and blows cold, and gets colder when the recirculate button is turned on, but after some city, stop and go driving, or sitting in traffic, the cold air turns a little warmer, and a little more humid.

What is going on?

Thanks,

 

Probably just heatsoaking the condensor to the point of inefficiency. Get some big 19" blades and wire 'em up to come on high speed, and you'll feel a big difference.
~Tom
PS- I have not done this, just relaying info gathered over the years.

 

where would I mount them?

 

Its normal to get a smidge less cooling (5-10 deg) at a standstill as opposed to rollin down the road. First of all, you've got less airflow through the condenser, and thus less heat rejection, secondly you're not turning the compressor as fast, and therefore getting less refrigerant flow/pressure.

 

I don't know what type FMIC you're using, but the GReddy I'm using & the Apexi, I think, requires the a/c condenser to be laid almost flat under the FMIC/radiator. What I did was mount 2 10" fans directly onto the condenser, controlled by a relay hooked to the compressor power wire. I also cut some circular holes into the undertray to get air to the fans.

As for your question, when the a/c is turned on, the pressure slowly builds up in the system & unless the condenser is getting enough cooling airflow to lower the pressure, the efficiency suffers & so does the cooling capability of the system.

 

Gag. I am worse off because I have an underdrive pully system so there is less power to the AC.

I will do the fan mod sometime in the future...