2005 Accumulator Schrader Valve question

[03catburban]

That's how it's designed you can change the pressure switch without having to recover the refrigerant

Being a technician, them being designed like that has saved me alot of time on the job

 

[nonickatall]

That's how it's designed you can change the pressure switch without having to recover the refrigerant

Being a technician, them being designed like that has saved me alot of time on the job

How often does this pressure switch fail? I'll order 20 pieces right away...

No seriously, in all my years as a car technician I've definitely had 2 faulty pressure switches, but 20 faulty air conditioning condensers, 5 faulty compressors, faulty lines, leaks, electronic problems and so on.

And if your pressure switch is leaking, you don't know what amount of cooling refrigerant is left in the system, so when you do it in the right way, you have to evacuate the system, measure the amount of cooling refrigerant, set the system to vacuum, to remove humidity and refill the system again, what an automated air conditioning service system, what I have in my garage, all do automatically.

So I really wonder, why the manufacturer build in this valve, which has absolutely no sense.

But if they have it.. Great ...

 

[OR VietVet]

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...

I have never ever seen, on GM vehicles at least, an accumulator that did not have a shrader valve at that port.

 

[OR VietVet]

How often does this pressure switch fail? I'll order 20 pieces right away...

No seriously, in all my years as a car technician I've definitely had 2 faulty pressure switches, but 20 faulty air conditioning condensers, 5 faulty compressors, faulty lines, leaks, electronic problems and so on.

And if your pressure switch is leaking, you don't know what amount of cooling refrigerant is left in the system, so when you do it in the right way, you have to evacuate the system, measure the amount of cooling refrigerant, set the system to vacuum, to remove humidity and refill the system again, what an automated air conditioning service system, what I have in my garage, all do automatically.

So I really wonder, why the manufacturer build in this valve, which has absolutely no sense.

But if they have it.. Great ...

With ANY a/c leak, you have no idea how bad the leak is till you recover the refrigerant and weigh what is removed. I can't help it if the switch/port design makes no sense. It was never a different design, since I started in and was in the shops. You have never seen me suggest here that anyone just add refrigerant and can have complete confidence that the system was exactly correct as to whether it was full or over full. I always recommend complete recovery and refill as per specs. Unless the orifice and accumulator are less than 1 year old, I always recommend those parts be replaced if system is opened up and flush the system out. Overkill, sure, but it is my comfort zone and if someone wants me to stand behind a paid repair, that is what I did.

 

[mattbta]

@OR VietVet The shop that replaced my high side and then leaked out and needed a low side which they replaced said the only way to know if it was low on refrigerant would be to evac and weigh (thus incurring their service fee). I asked if they could just put gauges on it for a rough idea and the balked. What if I get those gauges you recommended in my thread -- would that be enough to know if it was out of spec?

 

[OR VietVet]

@OR VietVet The shop that replaced my high side and then leaked out and needed a low side which they replaced said the only way to know if it was low on refrigerant would be to evac and weigh (thus incurring their service fee). I asked if they could just put gauges on it for a rough idea and the balked. What if I get those gauges you recommended in my thread -- would that be enough to know if it was out of spec?

Gauges give you pressure readings, ambient temperature sensitive, of the refrigerant in the system, at static and also while the system is working and cycling. The only true way to know if you have too much or too little refrigerant in the system is to weigh it and monitor it during the charging process. A shop will balk at just a simple, "top off" because, IMO, 2 things. To top off can still either undercharge or overcharge the system and that can effect the efficiency of the system and can also do internal damage. Then when the shop accepts money for that process, you want to hold them liable. Also, to just top off the system, does not allow the tech to remove all moisture that could be in the system. When an a/c system is put in a vacuum, moisture will boil internally and the vacuum pump then removes that moisture as a gas. The longer it is on a vacuum pump, the more moisture is removed.

If I ran a shop, and when I did run shops, if the accumulator was at least 1 year old, I insisted on replacing it. It is the moisture filter for the system. Moisture does damage to the internal workings of the system. If the customer refused the replacement, I made sure there was a disclaimer on the work order and signed by the customer. You have to remember that I came from a hot and humid climate in KC, Mo., to the PNW. Not as much a/c work here in the PNW but gobs of it in KC, Mo. There was a time, during the changeover from R12 to R134A refrigerant, that I had backup gauges for both systems because I could not take a chance of not having the correct equipment for the a/c work I did and the shop did. Because an a/c machine is typically used by multiple techs and therefore more chances of machine abuse, I kept and used my own gauges and vacuum pump and flush equipment.

 

[03catburban]

How often does this pressure switch fail? I'll order 20 pieces right away...

No seriously, in all my years as a car technician I've definitely had 2 faulty pressure switches, but 20 faulty air conditioning condensers, 5 faulty compressors, faulty lines, leaks, electronic problems and so on.

And if your pressure switch is leaking, you don't know what amount of cooling refrigerant is left in the system, so when you do it in the right way, you have to evacuate the system, measure the amount of cooling refrigerant, set the system to vacuum, to remove humidity and refill the system again, what an automated air conditioning service system, what I have in my garage, all do automatically.

So I really wonder, why the manufacturer build in this valve, which has absolutely no sense.

But if they have it.. Great ...

I have dozens of them over my career not just gm but mainly domestics

And i agree on recovery so you know how much is lost. But some people just want the a/c working on their box, nevermind the car is falling apart, so being flat rate I'd change switch on top off via pressures. Instead of not getting the job at all

And your doing good with 5 faulty compressors as a tech I know I've replaced over 100, may be my geography

 

[OR VietVet]

I have dozens of them over my career not just gm but mainly domestics

And i agree on recovery so you know how much is lost. But some people just want the a/c working on their box, nevermind the car is falling apart, so being flat rate I'd change switch on top off via pressures. Instead of not getting the job at all

And your doing good with 5 faulty compressors as a tech I know I've replaced over 100, may be my geography

Yep, the heat and humidity in Georgia keeps the a/c compressors hummin'.

 

[Blk00ss]

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

I have as well. In fact, I changed the switch on this one a while back. But I can see dye around it which leads me to bleieve its a slow leak from there

And yes, I also can see now that there is in fact a scrader valve behind the switch. Now I gotta find a PN for it