Electric AC, Installation. Options

[914Toy]

I have just finished installing an AC system with an electric 12V AC compressor with an "odd" collection of condensers which to my happy surprise appears to be working well or at least well enough! I committed to this some four or so weeks ago after much input from Steve, who has done most of the research, and had already bought most of his parts and tools to install a similar system to mine. He kindly lent me the tool to crimp the hose attachments, and the tools to charge the refrigerant into the system.

I purchased: 1) a new Benling 12V electric compressor from Steve, 2) a new Mini- cooler AC only evaporator from Southern Rods, 3) four used radiators/condensers (two 911 front condensers, and two early 2000’s Ford Explorer auto transmission oil cooler radiators from a wrecking yard (“El Cheepo”), 4) a new drier, also from Southern Rods, and 5) most of the Reduced Barrier hoses and fittings from Air Parts and some from Mesa Hose.

The pics show the compressor installed in the frunk behind my oil cooler shroud, the evaporator under the glove box, two 911 condensers “sandwiched” together with my Mazda engine oil cooler – all threes under the same slightly modified cowling with the 12” fan pulling/pushing the heated air through the bottom of the frunk, and a poor picture showing one of the modified Ford radiators (now AC condenser) with a 7” fan located in front of the passenger side rear wheel – the other similarly located in front of the driver side rear wheel. The drier is attached to the driver side frunk wall. I had the Ford 10”x7” radiator hose fittings modified to fit AC O ring seal hose fittings.

Other than simple challenges to fabricate the mountings for the compressor and the evaporator, the space and angles of available surfaces to attach the two condensers in the wheel wells were challenging but doable after much trial and error and adjustments to the aluminum brackets I fabricated.

The hose sizes and fittings were a challenge. The normal #10 and #8 hose fittings to the compressor are too bulky for my application, but Classic Retrofit came to the rescue supplying their efficient/elegant compressor/hose fittings. I learned that the modern Reduced (outside dimensions) Barrier (required to contain R134a refrigerant) hoses are more flexible, and need less space.

With the system running now, I measured the amps being generated by the alternator and the amps being absorbed by the compressor, all with a fully charged battery. The compressor is pulling 40 amps, and the alternator is generating 40 amps at 900 rpm engine idle speed, but 70 amps at 2000 and above RPM. I have a Denso 175 amp alternator on order, which should arrive tomorrow!
So we will see how all this performs later this week.

My grandson’s 3D printing skills produced three 45 degrees slip-on cold air “direction adjustment tubes” which is a nice finish for this application (see pics)!

The road test today was short but encouraging. I am joining the caravan from S. Cal Wed. morning to the Red Rocks Classic 2020, and expect to give this system a serious test through the desert!!

[ValcoOscar]

Nice Keith, can't wait to see how it works on your trip.

Be Safe...

(IMG:style_emoticons/default/popcorn[1].gif)

Oscar

[BPic]

Nice work. Please update us on this after your drive. Very interested in your thoughts.

Safe travels!

[wes]

I’m very interested in a AC setup as well looks good.

[Mueller]

Nice install, looking forward to a progress report.

[FL000]

Nice setup, and being electric definitely has the advantage of letting you put the compressor wherever is convenient.

Curious on the use of 4 condensers vs 1 - was that because of the space you had available or another reason? Also hadn’t thought of if before but interesting that those are good for the pressures in the system also.

Stay cool (IMG:style_emoticons/default/beerchug.gif)

[michael7810]

Very cool Keith

[Coondog]

Strong work...... (IMG:style_emoticons/default/first.gif)

[flat4guy]

Great idea - I saw this on the episode of Vintage Voltage but they never aired part 2 due to the Vid. Curious why so many condensers too?

[914Toy]

After I had bought the two 911 front condensers and had mounted them in front of my oil cooler, various “experts” suggested that they were not enough and less efficient then the new aluminum condensers, especially after Jonny pointed out that two together sharing the same air are only 10 to 15% better than one with the same air. This coupled with the already in place very effective Mazda oil cooler left me with little alternative than the space in front of the rear wheels for mounting additional condensing with fans.
If I was starting on a clean slate, I would design a frunk cowling to accommodate an oil cooler and an AC condenser that are angled so as to accommodate a wider AC condenser of modern design, say approx. 24” wide by 15” or so. That should be enough for our small volume cabins.

[913B]

Nice .... (IMG:style_emoticons/default/first.gif)

[jim_hoyland]

What a great installation (IMG:style_emoticons/default/smile.gif) The adaption to electric is a breakthrough for the 914s
Have a great trip to Durango...

[thelogo]

Hey keith .i new you were crazy when you sold me that engine ( still running strong )btw.

But wow. Thats some ac setup .
Vanity plates should read ..... Meat locker

[76-914]

It will be fine going there. They are forecasting some hot Wx on our return trip. Congrats and cheers. (IMG:style_emoticons/default/beerchug.gif)

[Chris914n6]

Get a cheap digital / cooking thermometer before the trip. A good system will see a 40F drop between ambient and output temps. Some of the newer cars I'm seeing a 50F drop.

Being such a small cabin and recirculating even if it sucks it will still cool good enough.

Are the condensers plumbed series or parallel?

[914Toy]

Get a cheap digital / cooking thermometer before the trip. A good system will see a 40F drop between ambient and output temps. Some of the newer cars I'm seeing a 50F drop.

Being such a small cabin and recirculating even if it sucks it will still cool good enough.

Are the condensers plumbed series or parallel?

In series, out the bottom and in the top of the next one.

[porschetub]

I have just finished installing an AC system with an electric 12V AC compressor with an "odd" collection of condensers which to my happy surprise appears to be working well or at least well enough! I committed to this some four or so weeks ago after much input from Steve, who has done most of the research, and had already bought most of his parts and tools to install a similar system to mine. He kindly lent me the tool to crimp the hose attachments, and the tools to charge the refrigerant into the system.

I purchased: 1) a new Benling 12V electric compressor from Steve, 2) a new Mini- cooler AC only evaporator from Southern Rods, 3) four used radiators/condensers (two 911 front condensers, and two early 2000’s Ford Explorer auto transmission oil cooler radiators from a wrecking yard (“El Cheepo”), 4) a new drier, also from Southern Rods, and 5) most of the Reduced Barrier hoses and fittings from Air Parts and some from Mesa Hose.

The pics show the compressor installed in the frunk behind my oil cooler shroud, the evaporator under the glove box, two 911 condensers “sandwiched” together with my Mazda engine oil cooler – all threes under the same slightly modified cowling with the 12” fan pulling/pushing the heated air through the bottom of the frunk, and a poor picture showing one of the modified Ford radiators (now AC condenser) with a 7” fan located in front of the passenger side rear wheel – the other similarly located in front of the driver side rear wheel. The drier is attached to the driver side frunk wall. I had the Ford 10”x7” radiator hose fittings modified to fit AC O ring seal hose fittings.

Other than simple challenges to fabricate the mountings for the compressor and the evaporator, the space and angles of available surfaces to attach the two condensers in the wheel wells were challenging but doable after much trial and error and adjustments to the aluminum brackets I fabricated.

The hose sizes and fittings were a challenge. The normal #10 and #8 hose fittings to the compressor are too bulky for my application, but Classic Retrofit came to the rescue supplying their efficient/elegant compressor/hose fittings. I learned that the modern Reduced (outside dimensions) Barrier (required to contain R134a refrigerant) hoses are more flexible, and need less space.

With the system running now, I measured the amps being generated by the alternator and the amps being absorbed by the compressor, all with a fully charged battery. The compressor is pulling 40 amps, and the alternator is generating 40 amps at 900 rpm engine idle speed, but 70 amps at 2000 and above RPM. I have a Denso 175 amp alternator on order, which should arrive tomorrow!
So we will see how all this performs later this week.

My grandson’s 3D printing skills produced three 45 degrees slip-on cold air “direction adjustment tubes” which is a nice finish for this application (see pics)!

The road test today was short but encouraging. I am joining the caravan from S. Cal Wed. morning to the Red Rocks Classic 2020, and expect to give this system a serious test through the desert!!

Impressed by results ,though there would be a higher power consumption ?

[Fosterjoejr]

[quote name='914Toy' date='Sep 7 2020, 03:50 PM' post='2849294']
I have just finished installing an AC system with an electric 12V AC compressor with an "odd" collection of condensers which to my happy surprise appears to be working well or at least well enough! I committed to this some four or so weeks ago after much input from Steve, who has done most of the research, and had already bought most of his parts and tools to install a similar system to mine. He kindly lent me the tool to crimp the hose attachments, and the tools to charge the refrigerant into the system.

I purchased: 1) a new Benling 12V electric compressor from Steve, 2) a new Mini- cooler AC only evaporator from Southern Rods, 3) four used radiators/condensers (two 911 front condensers, and two early 2000’s Ford Explorer auto transmission oil cooler radiators from a wrecking yard (“El Cheepo”), 4) a new drier, also from Southern Rods, and 5) most of the Reduced Barrier hoses and fittings from Air Parts and some from Mesa Hose.

The pics show the compressor installed in the frunk behind my oil cooler shroud, the evaporator under the glove box, two 911 condensers “sandwiched” together with my Mazda engine oil cooler – all threes under the same slightly modified cowling with the 12” fan pulling/pushing the heated air through the bottom of the frunk, and a poor picture showing one of the modified Ford radiators (now AC condenser) with a 7” fan located in front of the passenger side rear wheel – the other similarly located in front of the driver side rear wheel. The drier is attached to the driver side frunk wall. I had the Ford 10”x7” radiator hose fittings modified to fit AC O ring seal hose fittings.

Other than simple challenges to fabricate the mountings for the compressor and the evaporator, the space and angles of available surfaces to attach the two condensers in the wheel wells were challenging but doable after much trial and error and adjustments to the aluminum brackets I fabricated.

The hose sizes and fittings were a challenge. The normal #10 and #8 hose fittings to the compressor are too bulky for my application, but Classic Retrofit came to the rescue supplying their efficient/elegant compressor/hose fittings. I learned that the modern Reduced (outside dimensions) Barrier (required to contain R134a refrigerant) hoses are more flexible, and need less space.

With the system running now, I measured the amps being generated by the alternator and the amps being absorbed by the compressor, all with a fully charged battery. The compressor is pulling 40 amps, and the alternator is generating 40 amps at 900 rpm engine idle speed, but 70 amps at 2000 and above RPM. I have a Denso 175 amp alternator on order, which should arrive tomorrow!
So we will see how all this performs later this week.

My grandson’s 3D printing skills produced three 45 degrees slip-on cold air “direction adjustment tubes” which is a nice finish for this application (see pics)!

The road test today was short but encouraging. I am joining the caravan from S. Cal Wed. morning to the Red Rocks Classic 2020, and expect to give this system a serious test through the desert!!















Nice Work Keith!

Nice talking to you about the alternator, and have fun on your trip!

[76-914]

Joe Foster is new to our community. Long time Porsche Phile and he has a bunch of parts. I've bought from him and he is, well he is a good Joe. (IMG:style_emoticons/default/lol-2.gif) Sorry, I couldn't help myself. He is in Fontana. 775-771-3190

[gonzo54]

Keith, fasinating AC project and engineered like everything on your car. Looking forward to seeing it at Crystal Cove sometime-Have a fun trip to Red Rocks