Air Con fails after regas. Cause?

[Pupp]

2012 Seat Exeo, had new compressor fitted July 19 by local air con specialist after failed regas/service.

All fine until same place sticks their machine on to regas and reoil just prior to weekend. A/C promptly died over weekend, with no output apart from hot air. A morning of diagnostics later, I’m told the compressor solenoid has failed and, therefore, another compressor change is needed as the part is not separate.

That does not appear to tally with parts listed by ECP etc (high pressure solenoid valve?)

Accepting coincidences do happen, anyone know whether there is a non replaceable solenoid on a typical VAG compressor? Could this conceivably be caused to fail by a regas/service?

[GreenV8S]

That may be their way of saying it's a waste of money to refit the used compressor given the parts and labor cost. Or the web site may be wrong. I think I'd be inclined to trust the advice of an aircon specialist over a posting on an aftermarket web site. Given their advice that it's an integral unit, I'd be asking them whether they feel two years is a reasonable service life for the new compressor assembly they fitted. Assuming they haven't knowingly ripped you off by charging for parts not fitted, I think you just have to accept that problems happen and it isn't their fault. But if you approach them constructively, you may find they're able to discount some of their labor even if they can't help with the parts cost.

[Pupp]

Thanks for the response; as you’ve correctly surmised, I’m not especially acquainted with the air con components on the car nor really wanting to be… they seem pretty straight so we shall see

[Huskyman]

Pupp said:

2012 Seat Exeo, had new compressor fitted July 19 by local air con specialist after failed regas/service.

All fine until same place sticks their machine on to regas and reoil just prior to weekend. A/C promptly died over weekend, with no output apart from hot air. A morning of diagnostics later, I’m told the compressor solenoid has failed and, therefore, another compressor change is needed as the part is not separate.

That does not appear to tally with parts listed by ECP etc (high pressure solenoid valve?)

Accepting coincidences do happen, anyone know whether there is a non replaceable solenoid on a typical VAG compressor? Could this conceivably be caused to fail by a regas/service?

This could, and I mean could be too much oil in the system, as this can damage the compressor and stop the system from functioning correctly. Oil is not compressible and too much is a very bad thing. Only a certain amount of oil should be introduced into the system.
Ask the specialist the following:
1 How much oil was added during the compressor replacement?
2 Why did they add more oil during the service, and how much?

A simple evac will NOT remove the oil, only the gas and moisture. And like you said it was all ok until he did a regas and re-oil.

[Pupp]

Ok, thanks, I will explore that with then. Their kit looks pretty state of the art but I really have no idea what it does in the half hour or so the two ports are connected to it. I’d genuinely be surprised if that’s the issue as they claim to be prototype VAC designers for various car manufacturers as well as gaming posh kit.

I cannot get away from the thought, however, that two compressors have seemingly died right after system servicing…

[ruggedscotty]

Pupp said:

Ok, thanks, I will explore that with then. Their kit looks pretty state of the art but I really have no idea what it does in the half hour or so the two ports are connected to it. I’d genuinely be surprised if that’s the issue as they claim to be prototype VAC designers for various car manufacturers as well as gaming posh kit.

I cannot get away from the thought, however, that two compressors have seemingly died right after system servicing…

all the kit and nae idea as they say....

it could just be bad luck and the solenoid has failed. the solenoid is an electric valve - energise and the state changes it will pass refrigerant or not.

Your AC comprises of a compressor that takes the fridge gas and compresses it. passes it to a condensor that turns it to a liquid, and then that liquid passes through an expansion valve to turn it from a high pressure liquid to a low pressure liquid. The low pressure liquid goes to the evaporator and it makes that cold. the evap changes the liquid to gas that is then sucked back into the compressor to go through the cycle again.

Its a closed loop in that the fridge keeps going round and round. The is an oil thats added, that is used to lubricate the fridge pathway but not too much is added. the compressor doesnt like liquids as it works on gas. but the oil thats added is needed to lubricate the system.

Its very likely that the compressor solenoid has failed. and this part will probably be within the compressor and not servicable.

[Pupp]

Thanks for that very clear explanation; the compressor was supposed to be warranted for 2 years (of course at least a year of that was during covid restrictions so the car was being used a lot less); hopefully there will be a route through acceptable to both sides.