A/C clutch faulty, no cold air

Hi all,

Anyone here with experiences fixing the a/c clutch, expensive and/or difficult?

Cheers,
Vidar

May I ask why you are specifically interested in the clutch?

OK, If your problem is the clutch, there are two main failure modes.
1) The metallic clutch pads get worn. The "clutch" usually has shims to set the correct distance between the input shaft plate and the idler pulley plate when they are "relaxed". The gap between the two has to be close enough that the electromagnet can pull the plates together but far enough apart that they don't drag. When the plates get worn the gap gets too big for the electromagnet to pull the plates together and the clutch no longer engages. In this case all you need to do is re-shim the input shaft plate. In case you don't know, shims are just thin spacer washers of a particular thickness. The job entails removing the center lock nut in the middle of the input shaft plate, removing the plate, removing one of the thinnest shims on the shaft or removing a thick shim and replacing it with a thinner shim.
2) Burnt out / damaged clutch. This is unusual but can happen. This requires removing and replacing the electromagnet. It's only slightly more complicated than replacing the shims but you are up for the cost of the electromagnet.

Hi, thanks for the reply.

Turns out the compressor needs to be replaced. The A/C hadn't been properly serviced the last years.

Cheers,
Vidar

This post is not specifically aimed at Vidar, just a general comment.

You cant really 'service' an A/C system. It's not like your engine where you can do preventative maintenance, like changing the oil or spark plugs.
If it fails, it fails. There is nothing the owner can do to prevent it.
The A/C system is effectively sealed-for-life. A technician can check the performance of the system but usually the driver is the first one to find a fault (that it's not working). You can't prevent A/C failures only detect them (well for the most part).
I don't recommend getting the A/C serviced if you believe it's running well, it's a waste of time. If there is a problem with your A/C system you will probably be the first to know. They would NEVER fully inspect your system anyway (too time intensive but they will still say they did it). Again, they will only find a problem...not prevent one.
Could they find a small problem that could become a large problem? Well that's a numbers game...like the lotto! Maybe, maybe not. You could put a stone through the condenser the day after getting the A/C system serviced! Besides the systems wont activate without gas, preventing any further damage, like, running the compressor dry.

If you want your A/C working for the summer, check that its working at the end of winter. If you think it's not running as well at it should, sure, get it checked out. If you run it at the beginning of summer and it doesn't work you may need to wait, because the A/C places are busy with other people who left it too late too!

just a single comment to add. In the UK Citroen do offer an aircon 'service'. This probably won't check the function of the system . it is just sanitising the system to (hopefully) kill any bacteria in the filters to prevent or remove odours.

Thanks for your comments

So, a question: Is the mechanic right when he says that the AC lose 10-20% of the gas each year, and that needs to be replaced (= "servicing the AC")? He also claims that one reason for the compressor failing is that it needs to work harder with less than required levels of gas in the system.

I still need to replace the damn thing, just looking to learn something new

Cheers!
Vidar

Yes, the gas leaks out over time. You should have the A/C serviced every two or three years to regas and oil.

Run the A/C regularly, even in winter to help the oil lubricate the pump and it's seals.



There is a lot to read in the Citroen C3 - Should I use my A/C topic that may help you.

vidarm wrote: ↑Mon Jul 13, 2020 4:16 pm Thanks for your comments

So, a question: Is the mechanic right when he says that the AC lose 10-20% of the gas each year, and that needs to be replaced (= "servicing the AC")? He also claims that one reason for the compressor failing is that it needs to work harder with less than required levels of gas in the system.

I still need to replace the damn thing, just looking to learn something new

Cheers!
Vidar

The walls of the flexible hoses are the only part of the A/C system that you might expect refrigerant to leak from. There are two types of flexible hoses used in A/C systems. Reduced barrier and full or standard barrier. Reduced barrier are cheaper and smaller (in diameter) than full barrier. Reduced barrier hoses will leak refrigerant over time because they are permeable, but you are looking at a small amount over years and NOT 10-20%! Full barrier do not leak. You would have to look at the part number printed on the hose to see what type it is. No other part of the system is expected to leak refrigerant. The refrigerant CAN leak out of joints and seals and cracks BUT it's not EXPECTED to leak from there, that is considered a failure.
I have a 2004 Citroën C2 1.6 VTR that I have owned since brand new and it has NEVER HAD ANYTHING DONE to the air conditioning system. No service, no top up, no nothing and it still runs as well as the day I bought it. The C2 and C3 systems are identical!
So my C2 has lost NOTHING from the air conditioning system in 16 years! Read between the lines.
However, one of my C3's lost refrigerant overnight because one of the refrigerant lines rubbed on the engine mount and created a hole!! Sh!t happens.

With a loss of some refrigerant the compressor will work longer but not harder. With less gas comes less pressure and less workload. Instead of the system running down to temperature and stopping, the compressor will now continue to run longer, trying to get the temperature down but failing. Some systems will only let the compressor run for a certain amount of time anyway, for two reasons. 1) The evaporator will freeze up if run for too long. 2) Not enough gas in the system and it's just wasting it's time. When the loss of gas gets to a certain point, the compressor wont engage anyway. Those little computer things running our lives are pretty clever these days!
As I said, the driver will tell if the system is not working properly way before it could potentially become a problem. As if not getting cold wasn't a problem in the first place.

If you are loosing gas from your system then something is wrong, it's not "to be expected".

My point is there is very little the owner can do to prevent A/C failures. Yes, as Arfur says, running the A/C from time to time will circulate oil around the system and lubricate parts, but I cannot say that will guarantee that those parts wont fail. It is however the closest thing you can do as preventative maintenance for the A/C system...and you don't need to take it to a professional to do that.

If people wish to get their A/C serviced, just for piece of mind...then fine, I will not argue with that. Discretion is the better part of valour. While I might not recommend it, I am not saying it's a bad idea.

Can you find out why the compressor needs replacing? What part has broken?

Just for info, our 2011 C3 has never had anything done to its aircon. The car has done over 120,000 miles and the aircon still works fine.

Thank you for all your comments!

Is "servicing the AC" just a ploy from the garages, then? Here in Norway, it is "common knowledge" that you should refill the AC every 2-3 years, and not a word about leaky pipes or hoses - all AC systems should have this maintenance routine.

Best,
Vidar