: "The A-6 compressor output as high as 42,000 BTUs" Is that actually true??

08-14-13, 09:44 PM
Here is where I read it at: http://www.hemmings.com/hmn/stories/2006/10/01/hmn_feature32.html

It says:

One of their more popular successes was the design of the model A-6 compressor, which was used by General Motors for more than 25 years. The A-6 was Frigidaire's first axial designed compressor. This compressor used a cast-iron cylinder and heads with a steel case and "swash" plate. The A-6 designation related to its axial design and the fact that it was a 6-cylinder compressor unit. The interior of the compressor also had an oil pickup and sump system to lubricate the internal parts. The A-6 compressor will push out 27,000 BTUs at 2,000 rpm and as high as 42,000 BTUs at 4,000 rpm with a discharge rate of 240 p.s.i. That's enough cold air to cool a small house (most home window-mounted air conditioners are only rated from 5,000 to 12,000 BTUs). The compressor functions much in the same way an engine does but without the ignition and combustion strokes. An A-6 is rated at 1.5-inch bore with a 1.2-inch stroke and 207cc displacement. That's about 121/2 cubic inches. The A-6 is also highly adaptable. It can run in 6, 12 or 24-volt systems if you install the proper clutch coil. They are a pretty resilient unit too; they can turn consistently at 6,500 rpm all day without overheating

I wonder is that Engine R.P.M or Compressor R.P.M? And is this actually true? It seems like the old Caddy's should have been insanely cold!

08-15-13, 01:24 AM
^My college auto professor mentioned that it could cool a small house. I think I've got one kicking around the loft in the shed. It'll go in my Caddy when I get around to messing with the A/C system. :cool2:

08-15-13, 11:30 AM
I've heard that before, too.

08-15-13, 12:38 PM
Rolls Royce used them...

cadillac kevin
08-15-13, 01:10 PM
I wonder if I can put one for a 307 on my toronado? I'm sure the AC compressor (the old style that was long ans skinny) doesn't work anymore (although it was replaced approx 5 years before the car went into storage).

08-15-13, 09:39 PM
the old style that was long ans skinny

That IS the A6. Best that was ever made. I would bet it still works fine (but probably needs a charge).

08-15-13, 09:58 PM
That IS the A6. Best that was ever made. I would bet it still works fine (but probably needs a charge).

And possibly an oil change?

08-15-13, 11:08 PM
An automobile is a difficult environment to cool. First you have tremendous heat gain through large glass area in comparison to the passenger compartment volume. The you have all the areas that potentially allow air infiltration, once again relative to the passenger compartment. Finally the car is in motion, which increases air infiltration. It is actually amazing a car can be cooled if you think about, rather like a green house on wheels.

The Ape Man
08-18-13, 12:00 AM
CBod is right on. Add the relative sizes of condenser and evaporator compared to a stationary HVAC system to the equation. Those are the limiting factors.

Auto AC is also designed for fast recovery. Use after non-use car sitting in the hot sun. Stationary HVAC is designed to be just large enough to do the job on the worst day of the year for economy reasons.

I've had a few cars with engine transplants where the old GM "radial" compressor came factory equipped and I swapped to the axial. I did not notice any difference in AC performance whatsoever. My guess is either compressor is easily up to the task at hand. The axial compressors generally always held up better but many did not even use the C.C.O.T. where they were cycling a lot so comparison isn't direct.

Mercedes 126 models used the GM "radial" compressors installed close to the crankshaft. Those lasted 125K miles. I still think those units were built to several standards depending on application. Kind of like a TH-400 Cadillac transmission.

I need an editor : )