RE: Air conditioning question, more

[Don Muirhead <dmr@kwic.com>]

Mike:

In all seriousness...

Talked to one of my neighbors who went through this when he rebuilt 
customized his '38 Olds Coupe this morning.

He ended buying a system from a company called Vintage Air which produces 
custom light weight and highly efficient systems.  They are in the US 
(can't remember where - he dealt with them over the phone) and maybe you 
can pick their brains or perhaps they might have something that meets your 
needs.  He thinks he paid around $2,800 (US) but that was for heat, a/c, 
vents and all the plumbing.

He also told me that he almost installed the system that comes with the big 
John Deere and Case/IH tractors.  He said they are compact (1/2 size of 
automotive - twice the out-put), and easy to maintain but didn't have the 
time nor patience to pursue this option.

Hope this doesn't add further confusion to your quest.

Don Muirhead


-----Original Message-----
From:	Mike Arman [SMTP:armanmik@n-jcenter.com]
Sent:	Monday, July 12, 1999 4:59 AM

Turns out this has become a "hot" topic (groan!).

Got 16 e-mails this AM, this topic alone.

Here's what I learned so far:

Adapting aircraft systems isn't the answer. Cessna offered air conditioning
on 172s for a few years - it was a $12,000 option (!) and was just a plain
old belt-driven York compressor and automotive add-on system. Larger
aircraft systems would cost more than the car is worth, probably by several
orders of magnitude.

Ammonia systems aren't the answer either - the ammonia bromine (?) mixture
is poisonous and wildly corrosive, and I don't want to re-engineer the
entire system, just improve what's alredy there.

Removing the air conditioner entirely isn't the answer. It simply gets too
goddam hot (technical term) in the summer in Florida to simply pitch this
stuff, tempting as the idea sounds right now.

The original 4KW figure turns out to be somewhat high - it seems that 2HP
or 1500 watts, or about 12,000 BTU (YMMV) should do it. 1500 watts at 110
volts is 13.6 amps, and now we are talking realistic numbers both for
alternator output and power handling.

Given that, mounting a second "normal sized" alternator where the a/c
compressor used to live, and driving it from the a/c belt pulley shouldn't
be terribly difficult. Using a 2HP or 2.5HP DC motor (say from Burden
Surplus?) to drive the original a/c compressor could probably be done.
Mounting the motor/compressor system would be tough - it is big and heavy,
so the only home for it might be in the trunk, which would mean long hoses
and wires - another PITA. This isn't a good solution, but may be only the
least worst approach.

Talk to me about the "efficient scroll compressors" used on newer cars . .
. what's the deal on them? What cars are they used on? How much adaptation
would be needed beyond brackets and bolts? If I could even out the power
draw (smooth the pulses), I'd probably find a way to live with the rubber
flex hoses.

I do want my a/c to work, but don't want to destroy the drivability of the
car.

Mike Arman