Classic Retrofit: Lightweight Electric Air Conditioning

[Nditiz1]

Depends on how you have it wired. Per the instructions for a single condenser setup the relay is mounted on the smugglers box compressor carriage. Mine is mounted there, but when I added a second relay I opted to not overload it and ran a 2nd relay located in the rear wheel near the 2nd condensor. Do you have 1 or 2 relays? Also have you tested running power to them to make sure they spin up?

[Jonny H]

Originally Posted by rrcrawford70s

In my '73 911, I have the 2 condenser with fans on the drivers side rear wheel well.
Both fans are not working. They spin freely, nothing lodged or stuck.
Both fans use to come on automatically.

Where is the fuse or relay to confirm they are good. Anything else to check,

The 12V side of both fans should have been fused externally as per our wiring diagrams - usually by connecting back to the fuse box. Since you have the condensers in the rear, maybe it was connected to the rear fuse box?

It is also worth knowing that the relay coil supply (red wire into ECU) should also be fused as per our wiring diagrams.

The fans will only come on when the system pressure builds up so check you compressor is running. Without the compressor running, the fans will not run.

[ahendy]

Hi all, wow what a wealth of knowledge this thread is!

I've recently purchased the "half kit" for my 87 Convertible with a 3.6 engine in it. My original blower and evap are still perfectly fine so I figured this would simplify my install process a bit. However I'm running up against a couple of snags as I'm beginning to come up with an install game plan.

First, I have a secondary oil cooler in my front left fender, so I had planned to put the single condenser in the rear left fender, and also pipe in the belly pan/nose condenser that's existing on the car.

However upon inspection I've realized that the blower fan for the nose condenser is exactly where CR calls to mount the compressor in the half kit.

It feels like my options are the following:

a) Remove the nose condenser blower fan, mount the compressor in the intended spot, pipe in the front condenser, and just operate the system without a blower on the front condenser. (is it even worth piping it in if there's no fan on it?)

b) Remove the nose condenser blower fan, mount the compressor in the intended spot, and simply operate with just the single condenser in the rear wheel well. (I live in middle TN.. summers are very sticky. this feels less than ideal..)

c) Just buy another CR condenser/fan setup and mount both in the rear left wheel well (more expense, more custom bracketing, etc..)

or

d) find somewhere else for the compressor to exist, keep existing front condenser blower, pipe it all in, off to the races. anyone have any ideas on where it could go?

e) abandon the "half kit" idea and just buy the rest of the bits from CR to do a full install in the smuggler's box with the replacement blower and evap. (most $$$ but we know it'd work)

appreciate any input or thoughts folks have!

[Jonny H]

I would use our condenser as the primary and run the belly pan without the fan.

[ahendy]

Originally Posted by Jonny H

I would use our condenser as the primary and run the belly pan without the fan.

thank you! will do!

[ahendy]

Ok another question.. in terms of locations for the cabin and evap temp sensors..

Per page 55 in the install guide, the evap temp location makes sense to me but could someone provide some more detail as to where the cabin temp probe should go? I don't recognize the spot that is pictured..

[rollens]

Has anyone installed one of these units on a 1976 Porsche 912E? If so, what was the result? Like to hear both good and bad. Thx.

[Nditiz1]

As far as the install it should be the same as a 911. You may want to upgrade to a 150 amp alternator. I believe someone on 914world had a $500 conversion kit

[Bill5900]

Perhaps now there is an installer in the Boston area? Thx. Bill

[PICGC]

I have a CR system that the prior owner installed on my 1976 911S and have developed a problem. When I turn on the fan and push the blue button to turn on the AC, it will run well and then I will get a grinding noise that lasts a few seconds. It will go away for a while but every few minutes it comes back for a few seconds. Sounds like it is coming from right behind thr center dash, and the best comparison I can think of for the noise is one of the old metal pencil sharpeners from grade school that were mounted on the wall and you would stick a pencil in and turn the crank.

Has anyone experienced this? It does not do it if I just have the fan blowing, it is only if I have pushed the blue button to turn on the AC compressor. Thanks for any input or advice.

[mike sampsel]

Originally Posted by Jonny H

I would use our condenser as the primary and run the belly pan without the fan.

Jonny,

I've already connected my belly pan fan. What is your reason for not running the belly pan fan?

[Nditiz1]

@PICGC - When the noise happens can you hop out and check if its coming from the compressor? That seems like the only candidate since you never get the noise when just running the air box fan.

[PICGC]

Originally Posted by Nditiz1

@PICGC - When the noise happens can you hop out and check if its coming from the compressor? That seems like the only candidate since you never get the noise when just running the air box fan.

That is correct. I just completed a two day rally where I was in the car for 6+ hours a day, and if I just had the fan blowing everything was fine. When I pushed the blue button to turn on the AC the grinding/buzzing noise would come every few minutes. It lasts for about 3-5 seconds and then stops, but a few minutes later it would happen again, rinse and repeat.

I was going to contact Classic Retro to see but I thought I would ask here first, given the length of this thread it seems like a lot of others are running the electric AC and I thought someone else may have had the same issue.

Thanks!

[Jonny H]

Originally Posted by mike sampsel

Jonny,

I've already connected my belly pan fan. What is your reason for not running the belly pan fan?

Run the fan if you can. 'shendy' who asked the question, has a half kit where the compressor mounts in the battery position and clashes with the fan.

[Jonny H]

Originally Posted by PICGC

That is correct. I just completed a two day rally where I was in the car for 6+ hours a day, and if I just had the fan blowing everything was fine. When I pushed the blue button to turn on the AC the grinding/buzzing noise would come every few minutes. It lasts for about 3-5 seconds and then stops, but a few minutes later it would happen again, rinse and repeat.

I was going to contact Classic Retro to see but I thought I would ask here first, given the length of this thread it seems like a lot of others are running the electric AC and I thought someone else may have had the same issue.

Thanks!

The compressor when starting does 'shake' a little as it gets up to speed then it smooths out. Maybe the mount has moved and it's touching the car body. Have a wiggle on the compressor and see if there is enough clearance. The mounting bracket is adjustable.

[goldtele]

Originally Posted by Jonny H

Canepa.

Thank you I just received my dual condenser unit and am looking in the bay area as well for my 76 911.

[PICGC]

Originally Posted by Jonny H

The compressor when starting does 'shake' a little as it gets up to speed then it smooths out. Maybe the mount has moved and it's touching the car body. Have a wiggle on the compressor and see if there is enough clearance. The mounting bracket is adjustable.

I checked the bracket and there is enough clearance. I was able to video the sound - it is definitely coming from the smuggler's box. This video is a good example of what it sounds like (this is my first time uploading something to Youtube, let me know if it doesn't work). The compressor gets warm and the drier is hot to the touch with the AC on, if that makes a difference. If you would like me to video it from the other side looking down into the smuggler's box just let me know.

https://youtube.com/shorts/rNHIQM5jR3g?feature=share

[PICGC]

Originally Posted by PICGC

I checked the bracket and there is enough clearance. I was able to video the sound - it is definitely coming from the smuggler's box. This video is a good example of what it sounds like (this is my first time uploading something to Youtube, let me know if it doesn't work). The compressor gets warm and the drier is hot to the touch with the AC on, if that makes a difference. If you would like me to video it from the other side looking down into the smuggler's box just let me know.

https://youtube.com/shorts/rNHIQM5jR3g?feature=share

Just to add in case JonnyH or anyone has any ideas after watching the youtube video of the noise, I thought it might be low on coolant so I evacuated the system, put it on a vacuum (it held good vacuum pressure) and recharged with r134a. Still got the grinding sound. Hoping the compressor isn’t shot as it is only a couple years old and a new one is $$$$. Thanks for any input!

[hannu_911]

Did you add oil at any point?
Which oil did you add? PAG or POE?
What oil does the sign on your compressor say it has been prefilled with?

As you can see CR manual has been stating to use PAG oil until summer 2022, only version 1.5 changed the recommendation.
The label on my compressor says ZEROL ESTER 68SL 100ML.
It has been manufactured 2019.

I believe PoE and PAG don’t mix well and should not be used together.

Install manual v1.5
"System as shipped does not need compressor oil added. The compressor is pre-filled with PoE oil
but PAG oil can be used. Although this is an electric compressor, it does not need special oil as it is a
12V system. Please note that other systems we offer which run at higher voltages ( for example
400V EV systems) must use PoE oil."

Install manual v1.4A and earlier
"System as shipped does not need compressor oil added. The compressor is pre-filled with PAG oil.
Although this is an electric compressor, it does not need special oil as it is a 12V system. If extra
condensers are used more oil may be added."

[PICGC]

Originally Posted by hannu_911

Did you add oil at any point?
Which oil did you add? PAG or POE?
What oil does the sign on your compressor say it has been prefilled with?

As you can see CR manual has been stating to use PAG oil until summer 2022, only version 1.5 changed the recommendation.
The label on my compressor says ZEROL ESTER 68SL 100ML.
It has been manufactured 2019.

I believe PoE and PAG don’t mix well and should not be used together.

Install manual v1.5
"System as shipped does not need compressor oil added. The compressor is pre-filled with PoE oil
but PAG oil can be used. Although this is an electric compressor, it does not need special oil as it is a
12V system. Please note that other systems we offer which run at higher voltages ( for example
400V EV systems) must use PoE oil."

Install manual v1.4A and earlier
"System as shipped does not need compressor oil added. The compressor is pre-filled with PAG oil.
Although this is an electric compressor, it does not need special oil as it is a 12V system. If extra
condensers are used more oil may be added."

I have not added any oil to the compressor, but mine would have shipped with v1.4A install manual. I suppose I could look at doing that, was hoping to avoid pulling the entire compressor out as I can't read the label with it in the smuggler's box but I will give that a shot tonight.