2005 Accumulator Schrader Valve question

[Blk00ss]

I have found our AC leak. Its definitely coming from the connection where the electrical pressure switch connects to the accumulator. We already replaced the pressure switch, but it has a slow leak. I have 2 questions

1) Is there a Schrader valve behind where that electrical sensor plugs in? I assume so? Does anyone have PN?

2) I assume this is under pressure and when I thread the sensor off, I assume it'll leak/ spray? Maybe not if the Schrader valve wasn't leaking?

 

[Blk00ss]

Just realized this is in the wrong section. Our Tahoe is an '05

 

[Fless]

Moved it here for you.

 

[nonickatall]

Normally there is no valve behind the pressure switch in the accumulators.

The system is under pressure, if you unscrew the pressure switch, you lose the refrigerant.

So you have to evacuate the system, replace the pressure switch and then refill it. I usually seal the thread of the pressure switch with teflon tape from the plumbing trade, if if the pressure switch does not have a sealing surface with an O-ring

That seals reliably.

 

[OR VietVet]

More Information for GM GENUINE 1550156

Sorry, unless I misread the OP's statement, there is a shrader valve at the threaded male port of the accumulator, where the pressure switch threads on. If you look at the link description, it says-"includes seal". The seal is an o-ring inside the threaded female portion of the switch and there is a little nipple inside there too that pushes the spring loaded plunger on the shrader valve, that is threaded in to the accumulator male threaded stem.

 

[nonickatall]

I have never seen an ac accumulator with a Shrader valve beyond the switch. Shrader valves are normally the valves for filling the system. I wonder why a car manufacturer should ad a Shrader valve beyond the pressure switch, when you normaly more often evacuate the system in a regulary air conditioning service, then when exchange the pressure switch.

Additionally, when the switch is brocken, mostly it leaks. And when it leaks, you have to evacuate the system anyway, even if you could replace the switch without further loss of refrigerant.

But you never stop learning...

 

[OR VietVet]

I have removed and replaced switches at the accumulator without evacuating the system. Unless the design has changed.

 

[nonickatall]

I have removed and replaced switches at the accumulator without evacuating the system. Unless the design has changed.

Ok... interesting...

Propably at OEM but at normal Rockauto stuff? They build in a valve, nobody needs? Except when you change the pressure switch, which should, from the view of such manufacturer, immediately lead into a Akkumulator swap?

I will give them a call and tell them, where they can safe money, without negative impact at the customer...

I'll get a well-paid consulting contract with the Chinese...

 

[OR VietVet]

It was designed that way, on purpose, so that the switch, which has a higher failure rate than the switch at the compressor, could be changed easily without dumping the whole system.

 

[nonickatall]

It was designed that way, on purpose, so that the switch, which has a higher failure rate than the switch at the compressor, could be changed easily without dumping the whole system.

Come on. They reduce quality in the switch to save money and invest that money in a useless Shrader valve, what you would not need when the switch would be reliable?

Sound to me like German Politic...