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ApeRunner



Member Since: 16 Jun 2022
Location: Oxfordshire
Posts: 13

England 2012 Range Rover Westminster 4.4 V8 Barolo Black
Aircon -If It Ain’t Broke, Don’t Fix It!

Aircon advice please fellow Rangisti.
Aircon was struggling of late so today took advantage of a £36 Groupon re-gas at ATS. Prior to this the car was cooling but would take a while to generate a noticeable difference in a sun-soaked cabin. The re-gas was normal, system maintained a vacuum for the requisite 5 min (indicating no leaks). 780g of refrigerant removed and 890 replaced. Unfortunately since driving for 25-30 min with all permutations of cooling settings I can’t seem to get any cold air from any of the vents.
Engine seems to be idling quite high (maybe anticipating demand of compressor which not coming on line?).
Car is a 2012 4.4 TDV8 Westie.
Appreciate any help prior to taking it back to ATS. Anything you do with common compressor valve failure that I read about here?
Cheers in advance…

Post #637218 18th Jul 2022 4:11pm
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nicedayforit



Member Since: 11 Jun 2011
Location: Beside the Solway
Posts: 3972

England 2004 Range Rover Vogue Td6 Giverny Green

Interesting think about a regas and holding vacuum. Whilst the connected machine does test for leaks the one thing it doesn’t test for leaks are the schrader valves on the two connection ports, they have to be open whilst the vacuum is being applied so can’t be tested. I might be wrong but would have thought these two valves should be replaced with new as part of the regas process.
Are they leaking after your regas, who knows.

Post #637221 18th Jul 2022 4:31pm
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DrRob



Member Since: 16 Apr 2015
Location: Petersfield, Hampshire
Posts: 4302

United Kingdom 2011 Range Rover Vogue SE TDV8 Buckingham Blue

Sounds like a new compressor job to me. Same symptoms I had. Regassed. No leaks. Wouldn’t cool down. New compressor. Ice cold. Thumbs Up
Site sponsor Glenrands did mine Thumbs Up Gone to a good home: 2011 4.4 TDV8 Vogue SE Buckingham Blue with Ivory and clear glass = "Rory"
2025MY Defender D350 90 in Silicon Silver on coils
1974 Series 3 Lightweight = "Millie"
Many, many other Landies over the years
My preferred specialist: www.glenrands.co.uk
--------------------------------------------------

Post #637227 18th Jul 2022 5:07pm
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Phoenix



Member Since: 16 May 2022
Location: Gone
Posts: 1631

United Kingdom 

The refrigerant port valves are not normally changed during a degas/regas, I've seen a few leak but it's very rare.
A vacuum leak check over 5 minutes will only detect the very worst of leaks - one that would usually leave you with no refrigerant whatsoever to recover, even the 30 min. check stipulated by most manufacturers / accredited training establishments will only pick up relatively large leaks.

If the engine speed is raised due to the high cabin temperature, this usually indicates that the control side is functional and the problem is a restriction in the flow of refrigerant if the evaporator temperature isn't dropping, ideally you'd want to be looking at high & low side pressures which is only possible with a manifold set or an 'aircon machine' connected.

Post #637229 18th Jul 2022 5:31pm
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JayGee



Member Since: 27 Jul 2021
Location: London
Posts: 3200

United Kingdom 2012 Range Rover Vogue 4.4 V8 Orkney Grey

Delivered mine to Glenrands this very morning for a new compressor and to get a few other loose ends sorted. 2012 TDV8 Vogue (L322)

Post #637232 18th Jul 2022 5:49pm
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DrRob



Member Since: 16 Apr 2015
Location: Petersfield, Hampshire
Posts: 4302

United Kingdom 2011 Range Rover Vogue SE TDV8 Buckingham Blue

Mine rises the rpm as it gets going on start up on hot days Gone to a good home: 2011 4.4 TDV8 Vogue SE Buckingham Blue with Ivory and clear glass = "Rory"
2025MY Defender D350 90 in Silicon Silver on coils
1974 Series 3 Lightweight = "Millie"
Many, many other Landies over the years
My preferred specialist: www.glenrands.co.uk
--------------------------------------------------

Post #637233 18th Jul 2022 5:49pm
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ApeRunner



Member Since: 16 Jun 2022
Location: Oxfordshire
Posts: 13

England 2012 Range Rover Westminster 4.4 V8 Barolo Black

Thanks for all the responses. Very helpful. I’m not too clued up on aircon systems as I normally leave that sort of stuff to the professionals. What I don’t understand is, if I had a working compressor before the regas (temps weren’t ice-cold but indicated a functional system) why would it have failed completely after the refrigerant was changed?

Post #637239 18th Jul 2022 7:17pm
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appj62



Member Since: 07 Aug 2013
Location: Cheshire
Posts: 424

England 2006 Range Rover Vogue SE 4.2 SC V8 Buckingham Blue

After 16 years of trouble free A/C, my compressor sounds like a bag of nails and struggles to provide requisite cool air into the cabin. Not good in present conditions. Still, do have a sunroof to ease the pain. Previous cars:
S-Max 2007-2013 (only diesel I've had, good car but expensive when diesely bits go wrong, so what's the point?)
Galaxy 2001-2007
Mondeo Estate 1997-2001
Sierra Estate 1993-1997
Uno Turbo 1987 -1993
Fiesta 1984 - 1987
Fiat 127 1982 - 1984

Post #637242 18th Jul 2022 7:46pm
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garyRR



Member Since: 13 Mar 2021
Location: Hampshire
Posts: 1465

United Kingdom 

Check underneath with the air con on maximum for a constant drip of water from the air conditioning condenser (the drip is about level with the back of the driver seats). It may be blocked and freezing up.

Secondly, as seems to be the case with the 4.4 TDV8, most of the time, the problems are the same and few, which makes diagnosing quite easy.

If you've got an IID, I would also check in the live values the cabin temperature sensor (note there's several options. One gives 'N/A', one doesn't). It may however be worth cleaning the fan in the cabin temperature sensor assembly.

Thirdly, was it actually working / is working or is it actually intermittent (get the engine above 2,000 RPM for 5 seconds or so and see if 30 seconds or so later icy cool air starts coming out). The usual cause of all manner of A/C problems on the 4.4 TDV8 is the Refrigerant Control Valve (RCV) on the compressor however, to replace it, it involves removing the compressor and at over 10 years old now, it's best to just replace the whole thing, as a new compressor comes with RCV included.

DrRob, JayGee, others and myself have had different issues but all caused by the compressor. Glenrands or Harlands can do the job for you or if you're quite handy, you can replace it yourself and buy a holiday.

I did the job myself and wrote a step by step guide: https://www.fullfatrr.com/forum/post635799.html#635799

Hope this helps. 2015 Range Rover Autobiography 4.4 SDV8


Last edited by garyRR on 18th Jul 2022 8:40pm. Edited 2 times in total

Post #637251 18th Jul 2022 8:38pm
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Phoenix



Member Since: 16 May 2022
Location: Gone
Posts: 1631

United Kingdom 

ApeRunner wrote:
.... What I don’t understand is, if I had a working compressor before the regas (temps weren’t ice-cold but indicated a functional system) why would it have failed completely after the refrigerant was changed?


It depends on how the RCV in the compressor fails, clearly there is some mode of failure that was identified and a modified part made available, if it's a tolerance issue ('sticking') then it's possible that vacuuming the system has positioned the valve moving part(s) into the fixed part in such a way that the refrigerant flow is worse than before, it does sound like there was some form of restriction, possibly the RCV was allowing 'just enough' refrigerant through to create some differential and therefore cooling. It's also possible that a depleted system in conjunction with a malfunctioning RCV will actually work better than a fully charged system due to the greater differential pressures - a fully charged system could be behaving like an overcharged system if refrigerant is 'backing up' in the low side to the point where it is liquifying.
All the above is just thought experiments, I'd want to see a RCV in a working and failed state (and see some high & low side pressure readings) to give any meaningful diagnosis.

Post #637252 18th Jul 2022 8:39pm
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ApeRunner



Member Since: 16 Jun 2022
Location: Oxfordshire
Posts: 13

England 2012 Range Rover Westminster 4.4 V8 Barolo Black

Great stuff thanks, especially for the awesome write up GaryRR. I may summon up the courage to have a go at that.

Pheonix, your explanation of the failure mode of the valve sounds pretty plausible TBH. We shall see tomorrow when I hook it up to a mate's IID.

I shall update...

Post #637267 18th Jul 2022 10:13pm
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AJGalaxy2012



Member Since: 11 Jun 2018
Location: Gainsborough
Posts: 1464

United Kingdom 2012 Range Rover Vogue SE 4.4 V8 Bonatti Grey

holding a vacuum in a system that's normally under pressure isnt a really good test for system integrity. 'O' ring seals which under vacuum can be sucked into a seal area, pipe joint faces pulled together etc, when under pressure, they're pushed apart. BMW i3 Electric Car
2012 Full Fat RR 4.4 TDV8 (now gone)
2006 VW Touareg 3.0 TDi V6

Post #637275 19th Jul 2022 4:51am
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4434Morrison



Member Since: 02 Mar 2020
Location: Folkestone
Posts: 185

United Kingdom 2012 Range Rover Vogue SE TDV8 Santorini Black

When I first had my aircon recharged in my current 2012 4.4 TDV8 a couple of years ago they recharged it as a 4 zone system with 880g of refrigerant and the aircon would not blow cold. The problem it was a two zone system and only required 700g.

Once the refrigerant volume was reduced to 700g the aircon blew ice cold and still does.

I do a complete aircon recharge every spring as a matter of course and it's always ice cold during the hot summer months...

I mention this as the technician recharging the aircon at the time to 880g refrigerant, was unaware of the difference in the aircon refrigerant volumes depending on the two or four zone systems in the L322 and started traying to sell a new compressor and all sorts of additional and clearly unnecessary part replacements.

I mention this as a cautionary tale to evidence that refrigerant volume is critical on the L322. 2012 4.4 TDV8 Vogue SE Current
2015 E220 with AMG Sport Pack - Currently driven by my son
2010 3.6 TDV8 Vogue - Written off by my son

Post #637277 19th Jul 2022 6:13am
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Phoenix



Member Since: 16 May 2022
Location: Gone
Posts: 1631

United Kingdom 

AJGalaxy2012 wrote:
holding a vacuum in a system that's normally under pressure isnt a really good test for system integrity. 'O' ring seals which under vacuum can be sucked into a seal area, pipe joint faces pulled together etc, when under pressure, they're pushed apart.

That's the way it's dome with an 'aircon machine' typical in dealerships & fast-fits with tech's brandishing a F-GAS certificate for refrigerant handling and a three hour 'course' on how to operate the equipment.

If a leak is suspected, then it should be pressure tested with Nitrogen, for the reasons you state, the vacuum test is mandated for compliance with legislation, not diagnostics.

Post #637280 19th Jul 2022 6:31am
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AJGalaxy2012



Member Since: 11 Jun 2018
Location: Gainsborough
Posts: 1464

United Kingdom 2012 Range Rover Vogue SE 4.4 V8 Bonatti Grey

Yes I'm aware and it's necessary to vac the system out anyway to boil off any moisture and to remove the air.
I'm also amazed at the number of aircon recharge kits around with no gas compatibility checks, no lubrication and no vacuum for an empty system. BMW i3 Electric Car
2012 Full Fat RR 4.4 TDV8 (now gone)
2006 VW Touareg 3.0 TDi V6

Post #637282 19th Jul 2022 6:44am
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