A/C Condenser fan

[moab911]

I recently had the Air Conditioning on my 86' Carrera checked and charged and the shop told me that if I put a fan on the condenser I would get much better cooling. Is this true and if so what size fan should I use. Any information would be appreciated. Small dual fans etc. Thanks, Bruce

[Por_sha911]

There has been much posted over the last few years about spal fans on the rear condensor. Do a search and I'm sure you'll find plenty of info.

[moab911]

Thanks. I'll check.

[Mitch Leland]

Like Joe says, there's a ton of information that has been posted regarding the addition of adding fans to the rear condenser. I believe most people agree that they do help in stop and go traffic, but once under way they don't make a big difference. Certainly they are added weight where you don't want it.

I considered them, here's some information that I got out of the Summit catalog a year or so ago. I was going to use 2 of these. You need to balance CFM's against amps.

[jhubs]

Here is a thread that may help: How's your A/C holding up this summer?

[Hladun]

The condenser fan makes a huge difference. My A/C system has worked well for 6 years. (And if you think that the weight of the fan will affect your car....well let's just leave it at that)

Here's what I said in a post in 2003 when I did my system;

I've studied the system because I'm going to get the a/c working in my 78SC this summer. I think the big (but totally unnoticed) problem with 911 a/c systems is the lack of air flow through the condenser; particularly at idle. We all look at that engine fan and think it pushes a lot of air but it doesn't. At 6000 rpm the fan pumps about 3000 cfm and the engine draws about 300 cfm. At idle (1000 rpm) that's 550 cfm. That's an air flow of 4 mph through the trunk lid opening at idle. Not enough!

Get a 9" pusher electric engine cooling fan (J.C. Whitney) and mount it on the left side of the condenser. Check very carefully so you have enough room. This fan blows at 660 cfm and since what goes out has to come in, at idle you'll get 2X660 plus 550 = 1,870 cfm. That's about 13 mph air speed through the condenser. That should make a big difference in your a/c performance.

[jhubs]

Originally Posted by Hladun

The condenser fan makes a huge difference. My A/C system has worked well for 6 years. (And if you think that the weight of the fan will affect your car....well let's just leave it at that)

Here's what I said in a post in 2003 when I did my system;

I've studied the system because I'm going to get the a/c working in my 78SC this summer. I think the big (but totally unnoticed) problem with 911 a/c systems is the lack of air flow through the condenser; particularly at idle. We all look at that engine fan and think it pushes a lot of air but it doesn't. At 6000 rpm the fan pumps about 3000 cfm and the engine draws about 300 cfm. At idle (1000 rpm) that's 550 cfm. That's an air flow of 4 mph through the trunk lid opening at idle. Not enough!

Get a 9" pusher electric engine cooling fan (J.C. Whitney) and mount it on the left side of the condenser. Check very carefully so you have enough room. This fan blows at 660 cfm and since what goes out has to come in, at idle you'll get 2X660 plus 550 = 1,870 cfm. That's about 13 mph air speed through the condenser. That should make a big difference in your a/c performance.

He is 100% correct. I found that even the one 7" spal fan I installed made a big difference in the at-vent-temp in the cabin. Replacing the A/C hoses with US brand hoses (NOT OEM hoses), installing the passenger side floorboard air extension and installing the one puller fan changed the at-vent-temp from mid 40 degrees F to 39 degrees F. All for about $500 because I did not install the hoses or the fan myself..

Jerry

[moab911]

Thanks for the confirmation Jerry.

[moab911]

Mitch- Thanks for the web site information.