green sensor on reciever/dryer

Ga 951 · 05-26-2017, 06:27 PM

It was attached to the schrader valve beneath (until I broke the bugger off

). I thought it was an AC thermostat--#16 in the PET. Ordered one, and I was wrong. The thermo appears to screw into the condenser line just below the valve and above the lo press switch. As you may be able to tell, my setup is different.

Any ideas? Thanks

v2rocket_aka944 · 05-26-2017, 06:50 PM

That is the high-pressure safety switch fitted on late 86 and all 87+ models.
It shuts off the compressor if the system pressure gets too high.

Ga 951 · 05-27-2017, 02:25 AM

Thanks V2rocket. It didn't look like the lo press sw, so I thought it was the other part they have listed in the PET for the same position.

On close inspection, the valve housing appears to be welded into the condenser line. Will that whole valve housing screw out?

v2rocket_aka944 · 05-28-2017, 06:44 AM

pretty sure it's welded on there.

peteb · 01:53 PM

Hello,

FYI the green sensor is the switch that turns the fans on high when the AC high pressure is over 14 bar. The part number is 94465305300 (expensive). There may be aftermarket parts can be wired in. I'm looking into this for my car as this switch is not working on my car.

It is not the high pressure cut off switch. The sensor with two spade connectors on the same pressure line is the low-high combination cut off switch. Part number 95961313700 (not expensive). See TSB 8-8602.

Earlier 86 and 85.5 cars used the much less expensive thermostat to turn the fan on high when the high pressure temperature is over 52C after the condenser. PN 92861313101 (not expensive). It goes in kind of the same spot as the green sensor except it is screwed in at a horizontal angle 90 degrees off from your green sensor. The hose assemblies are different.

Peter

v2rocket_aka944 · 07-22-2017, 01:46 PM

good info, thank you for sharing, did not know it was for the fans. makes sense though.

Ga 951 · 07-22-2017, 03:14 PM

Peter,
Thanks for the response, I bought one from dealer and you are right about it being expensive

I had a hard time even finding one since they are NLA.
Hope you find an alternative.

peteb · 10-03-2017, 06:22 PM

Hi,

Just want to post that I found a replacement for the expensive Porsche high pressure fan switch part number 94465305300. This is the green sensor in the original posters photograph. I used a SW 9052C from universal air conditioner. This part is available from many sources for $20 or under. Search with Google....

The switch closes (turns on the fans on high) at 260 psi and turns back off at 210.

It comes with pig tails that I spliced into the leads cut off from my defective switch for the electrical connection. The sensor has a 1/4 flare connection and a valve depressor that fits in the same location as the original part for the high pressure connection.

The switch look just like the original in size shape and color.

Hope this helps someone.....

Peter

Bukowski · 10-04-2017, 02:42 AM

Thanks for asking this!

Ga 951 · 06:39 PM

Peter,
Thank you so much for the find!!
The dealer part I got ended up being defective ... ohmed closed at static psi (90 if IRRC). I'm currently running without the sw.
UPDATE: just ordered one online for $15

Ga 951 · 10-17-2017, 06:25 PM

UPDATE!!!

Thanks to Peter, all works as it is supposed too.

The sw I got screwed right on the fitting and sealed. It has 12 ga leads, so I soldered 16 ga extension wires on with 16 ga female spade connectors and hooked that puppy up.

Thanks again Peter! I am curious as to what process you used the find the correct alternative part, that will probably come in handy as these cars age and parts get harder to find.

mattdavis11 · 10-18-2017, 01:49 PM

It's a universal part, Ga 951. So long as the thread size that it attaches to is 7/16"-20 female flare, it will work on any vehicle that is so equipped. It is not 1/4".

Here are the part numbers from several different vendors.

AC Delco 1550203
Annex 23133
Autocomp Technologies 959052
Four Seasons 35832
Global Parts Distributors 1711797
NAPA 901409
NAPA TEM901409
Omega MT1493
Ranco 070538037F01
Santech MT1493
Visteon 320017

peteb · 10-21-2017, 08:01 PM

Hi,

The connection to this switch is definitely a 1/4 inch SAE flare. Note that flare connectors are sized by the nominal pipe size rather than thread specifications. I do agree that it has a 7/16x20 tread, but that is not its size, just its threads.

I did take me a fair amount of time to pick out this switch. I wanted to find one that would fit in the same spot as the original and have similar wiring. I was also looking for a pressure range that was typically for R134a AC systems. I picked up a used AC hose off Ebay to double check fitment before testing on my car.

There are other options with trinary AC switches that I considered including Porsche units. These are four wire switches that contain both the cutout and fan switches. Typically used in cars from the 90's to early 2000's. They would work fine, but, the wiring would look different that the original, and that always risks confusing future service efforts.

I did find that some of the equivalent parts available did not work as well for me a the part that I listed. There is some difference in the lengths of the valve core depressors on the switches. Some were too short to depress the Schrader valve core that lives in fitting on the car side. Of course, the Schrader valve could just be removed with the risk of surprising a future mechanic....

I'm glad my information could help,

Peter

Ga 951 · 10-26-2017, 06:42 PM

Thanks Matt and Peter,
I am always amazed at the knowledge shared on this forum!!

mattdavis11 · 10-27-2017, 01:49 PM

peteb, thanks for your clarification.

When I looked at the part on UAC's website, with whom I have an account and purchase the majority of my a/c parts, it said nothing about 1/4 flare. That's not the important part, most if not all are 1/4, but some are not 7/16-20, they might be 3/8-24.

Anyway, if anyone needs this part ($6.64 for me), or any others, let me know!