Educate me: A/C low side adapter

Reply Subscribe

Thread Tools

Search this Thread

Jun 20, 2015 | 07:04 PM

turbogoat

Thread Starter

AudiWorld Junior Member

Joined: Dec 2014

Posts: 45

Likes: 1

Educate me: A/C low side adapter

I get the part where I replace the low pressure switch with the Mastercool 82272 adapter and jumper the harness.

What I don't get is what happens to the low pressure switch when I'm done charging my system. Does it get left out permanently? If it gets reinstalled, how is that done without losing a bunch of r134a?

What piece of the puzzle am I missing?

Regards... Mike

1993 100 CSQ

Jun 22, 2015 | 05:48 PM

scargo1995

Audiworld Junior Member

Joined: Jun 2015

Posts: 16

Likes: 0

You simply unscrew the adaptor and reinstall the sensor. The adaptor should have a spring loaded valve stem like a tire valve, so a tiny bit of refrigerant will vent, but this is a normal loss.

Jun 22, 2015 | 05:50 PM

scargo1995

Audiworld Junior Member

Joined: Jun 2015

Posts: 16

Likes: 0

Quote:

Originally Posted by scargo1995

You simply unscrew the adaptor and reinstall the sensor. The adaptor should have a spring loaded valve stem like a tire valve, so a tiny bit of refrigerant will vent, but this is a normal loss.

Forgot to mention, un-jumper the connector and reconnect it to the sensor.

Jun 23, 2015 | 12:35 PM

turbogoat

Thread Starter

AudiWorld Junior Member

Joined: Dec 2014

Posts: 45

Likes: 1

Hi scargo1995, thanks for the info.

For clarification, when you say that the adapter has a spring-loaded valve in it, do you mean the port that the switch is currently screwed into? Should I be able to remove the switch from that port without losing any appreciable amount of the refrigerant that is residing in the system?

Thanks... Mike

Jun 23, 2015 | 01:18 PM

scargo1995

Audiworld Junior Member

Joined: Jun 2015

Posts: 16

Likes: 0

Yes, the switch is threaded onto the low pressure side valve (looks like a larger car tire type valve) and your adaptor should also have a plunger pin in it so that when you attach the refrigerant canister to it, it's center pin depresses the adaptor pin, which in turn then depresses the LP valve pin, opening the system to the refrigerant can. Because of this sequence, the process should be:

1) remove sensor wiring
2) remove sensor (16 mm)
3) check condition of O-ring - any cracks/tears or if hard/not-pliable, replace. It seals the sensor or adaptor so it needs to work properly.
4) make sure center pin of adaptor moves freely. If so, screw on adaptor and snug to make seal (mine, annoyingly uses a 17mm wrench, not easy to fit and not easy to find as a flare nut wrench.
5) jumper sensor cable
6) charge per refrigerant directions
Assembly is the reverse of removal (a little Bentley humor).