Air Con Not working

Frogwell · 10th July 2014, 07:56

Morning All,

After an ill advised foray into the world of Nissan X Trail ownership I am back using my 2002 CDT Tourer.

Amazingly the car flew straight through it's MOT after being left to sit in my garden for nearly three years. One downside however, is the air con seems to have stopped working.

To begin with it just wouldn't do anything, fair enough thinks I, it's been sat a while, probably not enough pressure to activate the tri switch. I took the car to ATS last week who did a pressure check which came back okay, so they charge it but report that the air con still doesn't seem to work. I test it and it seems sort of okayish. The air con is working, so my theory about the pressure and tri switch seems to have been correct. It's just not massively cold. I wasn't too bothered by that, and figured maybe it's just an age thing, and it's certainly blowing enough cold air for any temperature Scotland has to offer.

Roll on to yesterday, first time I'd used the car since last week and we're back to no air con - it's just not kicking in again. This leads to be suspect it's lost all it's pressure and the tri switch isn't kicking in.

So now we're onto the diagnosis stage again. My theory is the compressor has not faired well in the idle last few years, and while the seals were maybe good enough to get it through the pressure check and charge, the last few days were just too much for it to hold onto that charge. A failing compressor might also explain why the air con was not working at full efficiency just after the charge last week.

That's my thinking anyway - anyone care to concur, contradict or offer alternatives?

Thanks all.

SD1too · 10th July 2014, 08:07

Mark,

If the compressor is not engaging then your refrigerant is escaping, most likely because the seals have shrunk through lack of use for 3 years.

Search for a mobile air conditioning service company in your area. They will come to your house and carry out a proper system check, diagnosis and service. Your system should certainly be evacuated and a vacuum held for at least 30 minutes to purge the receiver/drier of stored moisture. Leak detection probes should be used to check for problem areas, including the seal on the compressor casing. The 'fast fit' outfits like ATS are not set up to do this, nor do they have the specialist knowledge.

Before you pick up the phone, check that your slow speed radiator fan is working by switching on the ignition and pressing the windscreen 'demist' button.

Simon

snorbitz · 10th July 2014, 08:14

The pressure tests done at a garage can only detect leaks that are reasonably significant. What the machine does is pressurise the system and hold that pressure for 30 mins. If the pressure drops within that time the recharge is aborted due to this drop in pressure. Attempting to find the location of a small pressure leak is not so simple. However a florescent dye can be injected into the system by a garage and then viewed under a ultra violet light. Any escaping dye will then show up. Other than that the only real moving part in a air con system is the compressor. This would also be my first suspicion, but I have been wrong in the past....... just ask the wife.

suffolk boy · 10th July 2014, 11:56

chances are your condensor is rotten.this item failed on both my ztt and my 75.just replaced the one on the 75 for a new one also replaced the seals.the new condensor was given a coat of car raidiator paint before fiting to protect it from salt which corrodes it.i did mine from start to finish in around 3 hrs.costs approx £45 for the condensor.£5 for the seals.£12 for the paint.£40 for the regas.nothing charged for the gas removal.and to finish it off £10 for a aircon bomb cleaner as the system had not been used in a while i got a horrid smell apon use.now as fresh as a daisy and nice and cool

Frogwell · 10th July 2014, 21:54

Thanks for the replies.

Simon - the slow setting on the radiator isn't working, not sure it ever has since I bought the car in 2008 to be honest. I only realised it was supposed to have a slow setting when I was looking through the forum last week when I realised the air con wasn't switching on and I found information on the resistor. I've picked up a heavy duty resistor which I was intending to fit this weekend, but I might get a new condenser and fit it at the same time. I had a look at my condenser this evening and quite a few of the lower fins appear to be missing so I suppose it could probably do with replacing anyway.

I noticed Haynes said to remove the radiator to replace the condenser, but looking at other threads on here I'm not sure that would be necessary once the bumper and slam panel are off. Anyone know if this is the case?

SD1too · 11th July 2014, 08:47

Quote:

Originally Posted by Frogwell

... the slow setting on the radiator isn't working ... I realised the air con wasn't switching on ..

The loss of slow speed fan won't prevent your air conditioning switching on. It will cause the air delivery to be warmer when the car is stationary or moving slowly. If the compressor doesn't engage from the start, you either have no refrigerant or an electrical fault.

Quote:

... I might get a new condenser and fit it at the same time ... quite a few of the lower fins appear to be missing so I suppose it could probably do with replacing anyway.

If I were you I would leave that for now. Get your radiator fan working then call out a mobile specialist to purge the system of moisture as I described in my last post. After all, it has been standing for three years. There's a good chance that your problems will then be over. If the air delivery is still warm with the radiator fan running, only then turn your attention to the condenser (the system can be evacuated there and then ready for the work).

Simon

Frogwell · 11th July 2014, 09:39

Hi Simon, Yes, I worked out that it was the low pressure causing the tri switch not to engage that was the problem, the fan resistor was just as aside I discovered while reading posts about air con problems.

I was just about to order a new condenser, but I'll hold off on that until I've changed the fan then. I suppose removing the bumper etc will be a lot easier the second time anyway (if a new condenser turns out to be needed).

Will the slow speed fan come on with the demist button even if the pressure is low?

Also, if I've lost all my pressure, will I still need to get the system purged prior to replacing the condenser?

Thanks,

Mark

SD1too · 11th July 2014, 11:34

Quote:

Originally Posted by Frogwell

Will the slow speed fan come on with the demist button even if the pressure is low?

Ah, a good question. We've looked into this before and I seem to remember that the answer is yes for the petrol engines and no for the diesel.

Quote:

Also, if I've lost all my pressure, will I still need to get the system purged prior to replacing the condenser?

You won't need to get the system evacuated if it's completely empty. After disconnecting the old condenser you should cap the open pipes to prevent moisture ingress. Then, after fitting your new condenser, I advise a minimum 30 minutes of vacuum before recharging with refrigerant as said above.

Simon

Evansabove · 16th July 2014, 13:44

Just noticed that your car is an 02 which I believe has a three speed fan and NO resistor. Check that you have a resistor before trying to replace it. There are pictures galore on here, probably from Arctic.
Good luck

John

Frogwell · 27th July 2014, 08:03

Thought I should update this - Not being able to find any air con specialists near me I thought I'd go down the condenser replacement route and see how far that got me. I removed the old condenser and it had several large splodges of green dye across the fins, so clearly it was leaking. I put the new condenser on along with new seals, took it back to ATS who recharged it and I now seem to have air con again! It's lasted 5 days now so I assume the condenser was the only leak.

John, my car does have the resistor, not sure if it was a factory fit or a recall or what, but I replaced it with a hefty gold unit and now I have a two speed fan!

The downside is the horn no longer works, which is annoying as I didn't even undo any of the wires, opting to move the bumper to one side. I assume I've either pinched a wire somewhere or got a dodgy connection. Bumper off time again I suppose.

Thanks all!

10th July 2014, 07:56	#1
Frogwell Regular poster '02 Rover 75 Tourer Diesel Join Date: Sep 2008 Location: Comrie Posts: 96 Thanks: 2 Thanked 8 Times in 2 Posts	Air Con Not working Morning All, After an ill advised foray into the world of Nissan X Trail ownership I am back using my 2002 CDT Tourer. Amazingly the car flew straight through it's MOT after being left to sit in my garden for nearly three years. One downside however, is the air con seems to have stopped working. To begin with it just wouldn't do anything, fair enough thinks I, it's been sat a while, probably not enough pressure to activate the tri switch. I took the car to ATS last week who did a pressure check which came back okay, so they charge it but report that the air con still doesn't seem to work. I test it and it seems sort of okayish. The air con is working, so my theory about the pressure and tri switch seems to have been correct. It's just not massively cold. I wasn't too bothered by that, and figured maybe it's just an age thing, and it's certainly blowing enough cold air for any temperature Scotland has to offer. Roll on to yesterday, first time I'd used the car since last week and we're back to no air con - it's just not kicking in again. This leads to be suspect it's lost all it's pressure and the tri switch isn't kicking in. So now we're onto the diagnosis stage again. My theory is the compressor has not faired well in the idle last few years, and while the seals were maybe good enough to get it through the pressure check and charge, the last few days were just too much for it to hold onto that charge. A failing compressor might also explain why the air con was not working at full efficiency just after the charge last week. That's my thinking anyway - anyone care to concur, contradict or offer alternatives? Thanks all.

10th July 2014, 08:07	#2
SD1too Doesn't do things by halves Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model. Join Date: Mar 2007 Location: Former Middlesex Posts: 20,416 Thanks: 1,587 Thanked 3,749 Times in 3,181 Posts	Mark, If the compressor is not engaging then your refrigerant is escaping, most likely because the seals have shrunk through lack of use for 3 years. Search for a mobile air conditioning service company in your area. They will come to your house and carry out a proper system check, diagnosis and service. Your system should certainly be evacuated and a vacuum held for at least 30 minutes to purge the receiver/drier of stored moisture. Leak detection probes should be used to check for problem areas, including the seal on the compressor casing. The 'fast fit' outfits like ATS are not set up to do this, nor do they have the specialist knowledge. Before you pick up the phone, check that your slow speed radiator fan is working by switching on the ignition and pressing the windscreen 'demist' button. Simon __________________ "Whatever is rightly done, however humble, is noble." Sir Henry Royce.

10th July 2014, 08:14	#3
snorbitz Avid contributor Rover 75 CDT Connoisseur SE Join Date: Mar 2014 Location: Wolverhampton Posts: 159 Thanks: 14 Thanked 18 Times in 17 Posts	The pressure tests done at a garage can only detect leaks that are reasonably significant. What the machine does is pressurise the system and hold that pressure for 30 mins. If the pressure drops within that time the recharge is aborted due to this drop in pressure. Attempting to find the location of a small pressure leak is not so simple. However a florescent dye can be injected into the system by a garage and then viewed under a ultra violet light. Any escaping dye will then show up. Other than that the only real moving part in a air con system is the compressor. This would also be my first suspicion, but I have been wrong in the past....... just ask the wife. __________________ A Married man should forget his mistakes. There's no use in two people remembering the same thing. https://badges.fuelly.com/images/sig-uk/292531.png

10th July 2014, 11:56	#4
suffolk boy This is my second home fiat panda Join Date: Sep 2009 Location: haverhill Posts: 6,720 Thanks: 96 Thanked 586 Times in 526 Posts	chances are your condensor is rotten.this item failed on both my ztt and my 75.just replaced the one on the 75 for a new one also replaced the seals.the new condensor was given a coat of car raidiator paint before fiting to protect it from salt which corrodes it.i did mine from start to finish in around 3 hrs.costs approx £45 for the condensor.£5 for the seals.£12 for the paint.£40 for the regas.nothing charged for the gas removal.and to finish it off £10 for a aircon bomb cleaner as the system had not been used in a while i got a horrid smell apon use.now as fresh as a daisy and nice and cool __________________ fiat panda 1.2 eco

10th July 2014, 21:54	#5
Frogwell Regular poster '02 Rover 75 Tourer Diesel Join Date: Sep 2008 Location: Comrie Posts: 96 Thanks: 2 Thanked 8 Times in 2 Posts	Thanks for the replies. Simon - the slow setting on the radiator isn't working, not sure it ever has since I bought the car in 2008 to be honest. I only realised it was supposed to have a slow setting when I was looking through the forum last week when I realised the air con wasn't switching on and I found information on the resistor. I've picked up a heavy duty resistor which I was intending to fit this weekend, but I might get a new condenser and fit it at the same time. I had a look at my condenser this evening and quite a few of the lower fins appear to be missing so I suppose it could probably do with replacing anyway. I noticed Haynes said to remove the radiator to replace the condenser, but looking at other threads on here I'm not sure that would be necessary once the bumper and slam panel are off. Anyone know if this is the case?

11th July 2014, 09:39	#7
Frogwell Regular poster '02 Rover 75 Tourer Diesel Join Date: Sep 2008 Location: Comrie Posts: 96 Thanks: 2 Thanked 8 Times in 2 Posts	Hi Simon, Yes, I worked out that it was the low pressure causing the tri switch not to engage that was the problem, the fan resistor was just as aside I discovered while reading posts about air con problems. I was just about to order a new condenser, but I'll hold off on that until I've changed the fan then. I suppose removing the bumper etc will be a lot easier the second time anyway (if a new condenser turns out to be needed). Will the slow speed fan come on with the demist button even if the pressure is low? Also, if I've lost all my pressure, will I still need to get the system purged prior to replacing the condenser? Thanks, Mark

16th July 2014, 13:44	#9
Evansabove Loves to post Rover 75 CDT Conn SE Join Date: Mar 2008 Location: Bournemouth Posts: 272 Thanks: 1 Thanked 6 Times in 6 Posts	Just noticed that your car is an 02 which I believe has a three speed fan and NO resistor. Check that you have a resistor before trying to replace it. There are pictures galore on here, probably from Arctic. Good luck John

27th July 2014, 08:03	#10
Frogwell Regular poster '02 Rover 75 Tourer Diesel Join Date: Sep 2008 Location: Comrie Posts: 96 Thanks: 2 Thanked 8 Times in 2 Posts	Thought I should update this - Not being able to find any air con specialists near me I thought I'd go down the condenser replacement route and see how far that got me. I removed the old condenser and it had several large splodges of green dye across the fins, so clearly it was leaking. I put the new condenser on along with new seals, took it back to ATS who recharged it and I now seem to have air con again! It's lasted 5 days now so I assume the condenser was the only leak. John, my car does have the resistor, not sure if it was a factory fit or a recall or what, but I replaced it with a hefty gold unit and now I have a two speed fan! The downside is the horn no longer works, which is annoying as I didn't even undo any of the wires, opting to move the bumper to one side. I assume I've either pinched a wire somewhere or got a dodgy connection. Bumper off time again I suppose. Thanks all!