Air con service - compressor clutch failure

[SD1too]

Originally Posted by mmarks

I couldn't get to the compressor wiring to check the voltage, but the relay isn't switching off and on do I assume it is energised.

You really need to get to the feed to the compressor clutch, or the output of the relay contacts. With the clutch cycling and engine running isn't there too much noise to hear the relay properly? Sometimes it's possible to feel it operating, but it's not easy in an engine bay. The proper reliable way to test it is by voltage measurement.

Halfords wouldn't tell me how much gas they put in, just that 'it was according to specification'

Oh yeah. That's exactly the sort of evasive nonsense which tells me that they haven't charged your system properly.

You said that you chose Halfords because they use a machine, dye and oil. You don't need to go to Halfords for this. I use a small mobile company which is a family business. They evacuate the system properly using a vacuum pump and weigh the refrigerant with me looking on, so I know what's going in. They also have dye, leak detecting equipment and refrigerant oil.

I should have asked this at the outset. What's the service history of your air con. Michael? Has the compressor ever worked properly?

Simon.

[mmarks]

Thanks for the reply.

The aircon has never worked since I got the car.

As for the noise, to be honest the compressor is not noisy at all, I can hear the engine fan and I unplugged the relay and plugged it back on with the engine running and the aircon on, I heard a single clear click.

[SD1too]

Michael,

The problem is that you don't know how much refrigerant is present. You need to have confidence that you have the correct charge before you can start fault finding.

I would not be happy with Halfords' attitude. I would choose another company and ask them to evacuate the refrigerant and weigh it. If it's incorrect, get your money back from Halfords. If it's correct, you can proceed with checking the compressor clutch electrical circuit. There are many possibilities: the relay, the trinary switch and the clutch windings, but it would be unwise to spend time investigating these until you know that you have the correct refrigerant charge.

Simon.

[mmarks]

Thank you for the advice. I guess that leaves me asking if anyone can recommend an air con company in or near Southampton. Halfords are clearly no good and kwikfit have been slated so how do I know who to trust?

[Livermpj]

I used a mobile 1-man outfit. He had modern A/C servicing equipment, and was able to test for leaks with high pressure nitrogen, pull a vacuum to evaporate any moisture, then refill with the correct amount of gas (450g) and top-up the oil.

Everything was done carefully, he was able to explain every step, and clearly understood what he was doing.
I'd definately recomend finding a small, local specialist company.

PS. There must be a reason why the compressor clutch isn't holding. They're pretty strong, perhaps the system's been over-filled (now or in the past), which has caused hydraulic lock?

HTH, Pete.

[SD1too]

Originally Posted by mmarks

I guess that leaves me asking if anyone can recommend an air con company in or near Southampton.

I use the London branch of this company:

http://www.chillywillys.org/

They also operate in the south coast region and may agree to travel to Southampton. It's a two man band who are related.

Alternatively Google came up with these in your area so you could see how they answer your enquiry:

http://www.southamptoncarairconditioning.co.uk/

http://southampton-airconditioning-service.co.uk/

http://www.coolrunners-southampton.co.uk/

They all appear to do vehicle air conditioning and nothing else, which in my view is a promising sign. You don't want a "jack of all trades and master of none". Say that you want to know the weight of refrigerant extracted and the answer should be: yes, that's no problem.

Good luck and don't hesistate to come back to us Michael if you have any further questions.

Simon.

[Phil-T4]

Originally Posted by Livermpj

and was able to test for leaks with high pressure nitrogen

Nitrogen is ok for R407, R410 etc but for R134A which has a smaller molecular structure, he should have pressure tested with high grade Helium.

[mmarks]

I thought I would conclude the story with some good news!

I bought a pump/clutch from ebay (as per a previous link) for 30 quid and had a company called cool runners come to my house this morning.

The guy checked the system and confirmed that the clutch in the pump had burnt out (the rubber had just about completely perished).

He tested my replacement pump then removed the broken one, put my new one in & oiled & refilled the system (with the correct amount of refrigerant). He tested the whole system, oiled everything and checked for leaks.

He spent 2 hours on the car and obviously gave me a full aircon replacement and service as well as replacing the pump. To top it all, his total charge was £90. Well chuffed, I now have ice cold air con, made a useful contact and learnt not to use Halfrauds for their services again (at least, not the branch I went to).

Result!

Michael

[James.uk]

I bought a 2nd hand air/con pump from my local scrapyard about two years ago, they were on a shelf not on a car.. Cost me £60 and I got it as a spare = justincase...

Give them a ring if you get stuck:- 0161 366 9471 ... But I bet most scrap yards have some...
...

[SD1too]

Originally Posted by mmarks

... a company called cool runners come to my house this morning.

The guy checked the system and confirmed that the clutch in the pump had burnt out .... He tested my replacement pump then removed the broken one, put my new one in & oiled & refilled the system (with the correct amount of refrigerant). He tested the whole system, oiled everything and checked for leaks.

He spent 2 hours on the car and obviously gave me a full aircon replacement and service as well as replacing the pump. To top it all, his total charge was £90. Well chuffed ...

So you should be! That is indeed good service (and good value at £45 per hour).

I now have ... learnt not to use Halfrauds for their services again ...

I always urge club members to support the specialist small operators. They do cost a little more than the likes of Halfords and Kwik Fit, but you do get a proper, comprehensive service and not just a recharge and a shrug of the shoulders.

I'm really pleased that you're sorted out and that the forum has been useful to you.

Cheers,

Simon.