Air Conditioning Not Working After Being Charged

[JefferiesFarnol]

Hello Chaps,


I've just got my car back after having the leaking air conditioning fixed; I bought it last year and the a/c didn't work when I got it. They found that it was leaking from the condenser and have replaced it and done a pressure test etc. before refilling the gas. It was working perfectly when I drove it home last week and I could hear a noticeable fan or compressor sound that was never there before and stopped whenever I pressed the 'econ' button.


However, now it all seems to have stopped working again! The sound has gone and there is no change when I press 'econ'. I trust that the garage did the gas repair and pressure test properly so I think something else must have gone wrong to stop it working. The fuse is fine, could it be that since the air conditioning has not worked for a long time up until now, that the compressor worked briefly and then gave up the ghost?

[suzublu]

Check the fan is working, Aircon off, press demist and see if the fan works

Also, you can test via the trinary switch to see if the compressor engages https://www.the75andztclub.co.uk/for...ad.php?t=35567

[hogweed]

Probably 1% chance, but when my man replaced my clutch he left the wire off the connector on the compressor (at least I think that's where it was...)

[SD1too]

Hello Hector,

You have two choices. You can take the car back to the garage on the basis that their work has not corrected the original fault; non-working air conditioning, or you can book and pay for a mobile self-employed specialist to test your system, make a diagnosis and even offer a repair.

From my own experience I highly recommend the second choice. The air conditioning service which general garages offer usually amounts to pressing an "auto" button on a machine which cycles through the process of evacuation, vacuum testing and re-charging. Unfortunately when it comes to leaks, the vacuum testing can be misleading. Like you, I've had a car pass this test only to have lost all its refrigerant within 24 hours! A specialist's low pressure nitrogen test will reveal any leaks much more efficiently if escaped dye doesn't identify the source.

It's very unlikely that there will be anything wrong with your compressor.

Simon

[JefferiesFarnol]

Thanks for all your messages. The fan definitely works and blows normal non-ac air through the vents and I can change the speed with the button; this also works without the engine running.


It's good to know that it is not likely to be the compressor. Since it worked after being charged by the garage I think it may have just lost its refrigerant again, as you say, Simon. I'll get a specialist to come over and then report back!

[tourer]

Originally Posted by JefferiesFarnol

Thanks for all your messages. The fan definitely works and blows normal non-ac air through the vents and I can change the speed with the button; this also works without the engine running.


It's good to know that it is not likely to be the compressor. Since it worked after being charged by the garage I think it may have just lost its refrigerant again, as you say, Simon. I'll get a specialist to come over and then report back!

Suzublu meant the engine fan in front of the radiator, not the cabin heater fan.

[JefferiesFarnol]

Originally Posted by tourer

Suzublu meant the engine fan in front of the radiator, not the cabin heater fan.

Oh right, thanks. I'll check that.

[JefferiesFarnol]

Originally Posted by suzublu

Check the fan is working, Aircon off, press demist and see if the fan works

Also, you can test via the trinary switch to see if the compressor engages https://www.the75andztclub.co.uk/for...ad.php?t=35567

I did some reading up and just checked the fan, I seem to have the earlier three-speed fan with no resistor and the low speed does not come on. I tried the paper clip test and the high speed came on intermittently.



So am I right in thinking that the a/c will not work without the fan coming on? It sounds like I need to make sure I have Econ on until I get this fixed.



Obviously I now need to fix the fan one way or another. I feel like I could replace the brushes but it might be a lengthy job and I need the car for work during the week. The idea of a plug-and-play replacement is tempting, but £300 isn't!

[stevestrat]

Yeah, when the low speed goes on a 3 speed its usually the brushes. If you go down the route of replacing them make sure you get good ones not some unknown quality from Ebay! Best recommendation is Engineering Carbon Products: https://engineeringcarbonproducts.co...n-carbon-brush Ignore that the ad says KV6, a 3 speed fan is a 3 speed fan, model is irrelevant.

[SD1too]

Originally Posted by JefferiesFarnol

I did some reading up and just checked the fan, I seem to have the earlier three-speed fan with no resistor ...

I doubt it Hector because the 1.8 cars were not fitted with the 3 speed system.
If you can't see a resistor visible through the radiator grille you may have the early 2 speed system without a resistor. Alternatively you may be one of the few who has the resistor mounted out of sight.

You've reported that the trinary switch test results in the high speed operating intermittently. That's a classic sign of an open circuit resistor.

To answer your question, the air conditioning can still be activated with a faulty fan but it won't cool properly. Yes, you should use 'Econ' mode until you've repaired the fan.

Your next move should be to expose the fan motor. If it has two wires entering the casing it's a resistor system and if it has three it's a non-resistor system, both 2 speed.

Simon