S40 (New) AC : - Aircon Leak

nbuuifx · May 16th, 2012, 21:16

I've got an 2004 S40 2.0d. I've only had it since January and the aircon has never worked.

I had the car from my Dad and he tried twice to get the aircon to work, the garage he used just refilled and pressure tested the first time, all reported OK and off he went happy, but then two months later it wasn't working again.

He took it back and they did all sorts of checks - couldn't find anything, but replaced a couple of cheapish bits (filler valve etc) they refilled, pressure tested and did a sniffer test. All seemed OK.

Again approx 2 months later it no longer worked.

Around this time he took it in for some other work and they had to remove various parts of the front end so they had a better look round but still couldn't find any problems.

So I can be fairly sure it's run out of gas again, but what can I do?

My Dad said the garage blamed it on the test being a vacuum pressure test which can suck a small hole closed, then they pressurize the system with positive pressure which can open up the small hole. They are saying it must be a tiny leak to not show up with the sniffer and to take months to escape.

It'd be nice to have working a/c but it's quite expensive to top up and if it's only going to last 2 months then it's very expensive! Any advice?

Welton · May 17th, 2012, 10:35

The garage sound a bit lacking in knowledge to me.

The Vacuum 'test' is not a pressure test at all it is simply to remove moisture from the system if it has been stood empty for a while (gas leaks out, air gets in). Moisture in the system will freeze inside the pipework and cause lots of problems.

The proper Nitrogen test is carried out at approx 250Psi, being quite a small internal volume a tiny leak will show up quite quickly (within a few minutes). Tell-tale signs of a leak are small oil leaks around the pipework joints or brackets or oil staining on the condenser at the front.

A proper look with a UV lamp and some special eye glasses will show up refrigerant leaks as bright purple coloured spots - then you can really home in on the leak and spray some soapy solution around the joints etc and literally watch it blow bubbles.

I would be looking closely at the front mounted condenser first (this is a weak spot on these cars).

sprout99 · May 17th, 2012, 12:52

you shoud not be able to regas if machine detects a leak

ours was regassed a little while back but is very sporadic in it's working

I'm 99% certain ours is down to the compressor clutch disenaging
when it gets hot

Another very common across the volvo range and easily fixed.

v40bart · May 17th, 2012, 20:09

Well, Nitrogen molecules are a lot bigger then refrigerant. Nitrogen test is useless for micro leaks, corrosion on the condenser can cause aluminium to became porous. The pores are small enough to keep the Nitrogen in but refrigerant escapes through them. When my system was tested it passed flying colours but few weeks down the line the aircon is just slightly cool again (it was icy cold for the first two weeks). The only way would be to get your new condenser anodized to make it more resilient.

Mike Arnold · May 21st, 2012, 18:05

If you get it regassed then insist that they put UV dye in it. Kwik Fit will only do this if you argue with them. Others may do it automatically.

At least then you will be able so see where the leak is.

May 16th, 2012, 21:16	#1
nbuuifx Senior Member Last Online: May 1st, 2015 23:01 Join Date: Dec 2011 Location: Staffs	Aircon Leak I've got an 2004 S40 2.0d. I've only had it since January and the aircon has never worked. I had the car from my Dad and he tried twice to get the aircon to work, the garage he used just refilled and pressure tested the first time, all reported OK and off he went happy, but then two months later it wasn't working again. He took it back and they did all sorts of checks - couldn't find anything, but replaced a couple of cheapish bits (filler valve etc) they refilled, pressure tested and did a sniffer test. All seemed OK. Again approx 2 months later it no longer worked. Around this time he took it in for some other work and they had to remove various parts of the front end so they had a better look round but still couldn't find any problems. So I can be fairly sure it's run out of gas again, but what can I do? My Dad said the garage blamed it on the test being a vacuum pressure test which can suck a small hole closed, then they pressurize the system with positive pressure which can open up the small hole. They are saying it must be a tiny leak to not show up with the sniffer and to take months to escape. It'd be nice to have working a/c but it's quite expensive to top up and if it's only going to last 2 months then it's very expensive! Any advice?

May 17th, 2012, 10:35	#2
Welton Premier Member Last Online: Sep 14th, 2021 17:03 Join Date: Feb 2009 Location: Market Harborough	The garage sound a bit lacking in knowledge to me. The Vacuum 'test' is not a pressure test at all it is simply to remove moisture from the system if it has been stood empty for a while (gas leaks out, air gets in). Moisture in the system will freeze inside the pipework and cause lots of problems. The proper Nitrogen test is carried out at approx 250Psi, being quite a small internal volume a tiny leak will show up quite quickly (within a few minutes). Tell-tale signs of a leak are small oil leaks around the pipework joints or brackets or oil staining on the condenser at the front. A proper look with a UV lamp and some special eye glasses will show up refrigerant leaks as bright purple coloured spots - then you can really home in on the leak and spray some soapy solution around the joints etc and literally watch it blow bubbles. I would be looking closely at the front mounted condenser first (this is a weak spot on these cars). __________________ 2005 S40 T5 SE - Manual. Bilstein B4's. (For Sale) 2010 Citroen C4 1.6 HDi (bizarre Gearbox model). 2010 Renault Twingo (refreshingly simple) 2018 Infiniti Q30 1.6T Business Executive (what's this button do?)

May 17th, 2012, 12:52	#3
sprout99 Master Member Last Online: Sep 28th, 2015 03:33 Join Date: Dec 2011 Location: Durham	you shoud not be able to regas if machine detects a leak ours was regassed a little while back but is very sporadic in it's working I'm 99% certain ours is down to the compressor clutch disenaging when it gets hot Another very common across the volvo range and easily fixed. __________________ Peugeot 208 GTi Prestige BMW 330d M Sport + Mk2 Golf Gti G60....

May 17th, 2012, 20:09	#4
v40bart Master Member Last Online: Jun 14th, 2015 13:09 Join Date: Sep 2006 Location: London	Well, Nitrogen molecules are a lot bigger then refrigerant. Nitrogen test is useless for micro leaks, corrosion on the condenser can cause aluminium to became porous. The pores are small enough to keep the Nitrogen in but refrigerant escapes through them. When my system was tested it passed flying colours but few weeks down the line the aircon is just slightly cool again (it was icy cold for the first two weeks). The only way would be to get your new condenser anodized to make it more resilient. __________________ 2008 V50 2.0 D, silver, off-black leather interior, plod spec 320mm brakes and suspension, says 140 ps on the sticker but flies like proverbial off a shovell. NICE...

May 21st, 2012, 18:05	#5
Mike Arnold Master Member Last Online: Apr 15th, 2024 11:47 Join Date: Dec 2001 Location: Stockport, Gtr Manchester View Photos By: Mike Arnold	If you get it regassed then insist that they put UV dye in it. Kwik Fit will only do this if you argue with them. Others may do it automatically. At least then you will be able so see where the leak is. __________________ Mike Arnold. 1966 122S

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