Have they broken my air-con?

[Martyn_n]

Last tuesday I took my car in to have the Air-con regassed with the intention of having plenty of dye added so that I stand a chance of finding out where it is loosing the gas (It has taken about 7 weeks to leak out in the past).
Prior to taking it in I replaced the receiver / dryer myself, I didn't prime it with oil but told them what I had done.
I duly picked up the car in the afternoon and they advised me that they could not find the leak, which I didn't expect given that it is a slow leak, and that it showed no sign of a leak during the vacuuming and pressure test. They also commented that it was now blowing cold air. I took the car home and have not driven it since.
This morning I went to have a look under the bonnet to see if the system had held it's charge. It was immediately obvious that the clutch was not activating on the compressor and a bit of digging showed that the connector on the pressure sensor on the receiver dryer was incorrectly fitted and not making an electrical contect. Upon reconnecting it the clutch did engage so there is pressure present but no fluid appeared in the window of the dryer and more worrying the compressor made an awful rumbling noise. Looking at the paperwork they added 950g of refrigerant and 30ml of dye but only 1ml of oil (Should be 20ml i believe).
The compressor has never made this noise before so I was wondering if the lack of oil has killed it (Hopefully this isn't the case as it won't have been running because of the fault) moreover how on earth have they filled and tested the system with the fault on the pressure switch (Which I assume I put on whilst replacing the dryer).
I'll be going back to them but do not know if I have any chance of them accepting that they did the job badly, I at least want the £60 quid back.

Hopefully there is someone amongst us who can give me some advice as air-con is a bit of a black art to me.

 

[BlackC55]

When the gas is recovered out of the car not all of the oil is taken too. 1ml isn't much but I very much doubt it caused your issue.

Have you considered that the plug may have worked loose? It may have been ok at time of re-fill but worked loose (as it was not fully pushed in).

In the winter all AC systems will appear cold. It's all of the sensor values that are most important to look at so you know the system is working properly. On a Merc it's best to plug it in to a star to check these values.

TBH I doubt you will. Get your ££ back.

 

[BlackC55]

Lack of gas will also cause issues with the system if it has leaked out.

Remember it's against the law to fill a car's AC system up knowing it has a leak.

What car is it?

Most leaks come from the condenser itself.

I hope this helps.

 

[Martyn_n]

It's a 124, so not many sensors to check out. The guy at the garage also said that most leaks are at the condensor. I know that it is not strictly legal to fill a leaking system but I cannot see any other way of tracing the leak. Having listend to the compressor again I don't think it's terminal. Previously it has taken several weeks to stop working so I cannot see why there is no fluid visible in the sight glass on the receiver / dryer after a few days and about 20miles, so I'm not convinced it was regassed correctly but cannot prove it.
I've slept on it and won't be arguing for my money back but for peace of mind I will get the extra oil injected. Or I might just get them to vac it out and I'll change the condensor as a precaution, it may just save me the cost of multiple fills.
Thanks for advice olly.

 

[219]

You could always take it along to Kwik Fit and ask for an air con service there . They often have special offers but I believe they charge around £50 for this

IIRC , they offer a money back guarantee if they can't reduce the vent temperatures by more than 10 deg , or if it fails within a certain time ( 30 days ? ) .

There have been a number of positive reports on this forum from members who have used this service .

 

[Martyn_n]

The last two times I had it filled was at Kwikfit but I thought a "specialist" was the way to go given that this time I actually hoped to find the leak and get it fixed once and for all. I should have gone to kwikfit and just asked them to bung a bit more dye in as at least I could see that it had been re-charged when they did it last.

 

[BlackC55]

We get calls from the local kwickfit asking us where the AC service valves are located.

If they can't find them........

 

[joecash]

why would anyone use a tyre fitter to service a mercedes air-conditioning system that could cost thousands to put right if it is "mis-serviced"?

 

[Dieselman]

why would anyone use a tyre fitter to service a mercedes air-conditioning system that could cost thousands to put right if it is "mis-serviced"?

Cobblers.

It's a simple system and the machine does the work once connected up.

 

[Dieselman]

We get calls from the local kwickfit asking us where the AC service valves are located.

Isn't that just because the low pressure valve is hidden behind the flap?

 

[WhitwellMike]

Not sure why they can't find the leak if they have the right tools.

How To Find and Repair AC Leaks - EricTheCarGuy - YouTube

If the pressure is ok under test condition, but reduces over time, could it be the compressor pump? Stab in the dark.

 

[Martyn_n]

Not sure why they can't find the leak if they have the right tools.

How To Find and Repair AC Leaks - EricTheCarGuy - YouTube

If the pressure is ok under test condition, but reduces over time, could it be the compressor pump? Stab in the dark.

I'll check the link out. They seem to know what they are talking about, the problem is that the refrigerant leaks out over a period of about 7 weeks, and not a lot has to leak out for the pressure to drop to a point where the system shuts down and the leak stops. For this reason any leak is difficult to find as it is so minute and the tracer disperses due to airflow. The concensus seems to be that the condensor in front of the radiator can be considered almost a consumable. They are going to drain and re-fill it next week as I told them I wanted the correct level of oil adding (They initially said they wouldn't because "it will only leak out with the refrigerant" but I pointed out that I was not going to run it without the correct oil level), They will stick it on the ramp and have a good look for dye at the same time.

I'm still considering letting them drain it and i'll change the rad regardless.

 

[paul73mt]

I had a new company car some years ago (Astra G) and the compressor failed. They fitted a new one at a cost of about £1000 then after 1 week it packed up found out that the person who recharged it didn't put the oil in so vauxhall had to swallow the bill for the next one

 

[Martyn_n]

Hopefully mine has some oil in, but i'm leaving it turned off until the recharge because I can assure you this car is not having £1k spent on it!!

 

[Martyn_n]

I took the car back today and they have identified the source of the leak, not surprisingly it is the condenser.

A quick look has once again proved ebay as the best prices but can I have opinions on whether I should go for this, which seems a bargain;
MERCEDES BENZ E CLASS W124 AIR CON CONDENSER NEW | eBay

Or go for one with more warranty and a known manufacturer in this one;
VALEO condenser, air conditioning a/c ac air con radiator MERCEDES-BENZ 816901 | eBay
?

 

[GP801]

Unless you want to do it again in the near future go for a respected make. That Valeo looks pretty good for the money. A lot less than ECP unbranded one.

 

[jaymanek]

If you have changed the drier, you should have made it explicitly clear to them that they needed to add 30-40g of oil... They probably would have charged extra.

As it is they have just done an automatic service which measures oil it sucks out and puts back the same amount.

I doubt they have caused the issue, even if they had it would be difficult to prove.

p.s. if you change the condensor, more oil will need to be added again.

 

[markjay]

Why not take the car back to the garage, explain the situation to them politely, and ask for their opinion / advice? Without 'blaming' anyone or asking for a refund...

As a customer enquiring regarding issues with the car they just worked on, they are very likely to discuss it with you openly and provide some guidance without charging for it. They may even offer to carry a test or two (if applicable).

Most smaller garages would want to keep their customers happy and see them come back, and if you do not give them the feeling that they have already lost you as a customer anyway, they are likely to prove accommodating.