2005 Rover 75 Air-con

jj4091 · 14 Jul 2026

I have had the above 1.8 litre from new but it has been Sorned for the last 6 years and only done 28k miles. Everthing works perfectly except--
Got it back on the road at the weekend and noticed on a run that the air-con was not cooling. Does anyone know if it probably just needs to be re-gassed.
Thanks

Wayners · 14 Jul 2026

You start with recharge and see if it holds pressure.
Many garages advertise as working on air-conditioning but in my experience they have been useless and a waste of money.
It would be worth finding a local car air conditioning specialist .
They will advise.

Avocet · Wednesday at 1:44 PM

jj4091 said:
I have had the above 1.8 litre from new but it has been Sorned for the last 6 years and only done 28k miles. Everthing works perfectly except--
Got it back on the road at the weekend and noticed on a run that the air-con was not cooling. Does anyone know if it probably just needs to be re-gassed.
Thanks

I agree with Wayners. Assuming you've checked obvious things like fuses, the gas pressure in there is probably too low to allow the pump to cut in. The most likely explanation is gradual loss of gas over time. In particular, if not used regularly, the seals in the compressor can dry out a bit and let the gas past. Next most likely, is corrosion in the condenser (the big radiator-like thing at the front of the car), because that gets all the stone chips. In this country, I think more aircon systems tend to fail through LACK of use, rather than wearing out. 15 minutes a month (summer and winter) is a frequently recommended minimum.

A mobile air conditioning specialist is by far a better bet than your local "cooler aircon or your money back" chain store!

jj4091 · Wednesday at 3:08 PM

Avocet said:
I agree with Wayners. Assuming you've checked obvious things like fuses, the gas pressure in there is probably too low to allow the pump to cut in. The most likely explanation is gradual loss of gas over time. In particular, if not used regularly, the seals in the compressor can dry out a bit and let the gas past. Next most likely, is corrosion in the condenser (the big radiator-like thing at the front of the car), because that gets all the stone chips. In this country, I think more aircon systems tend to fail through LACK of use, rather than wearing out. 15 minutes a month (summer and winter) is a frequently recommended minimum.

A mobile air conditioning specialist is by far a better bet than your local "cooler aircon or your money back" chain store!

Thanks. Booked in to local garage for pressure and leak test and re-gassing

Stivino · Wednesday at 3:24 PM

It's a vacuum test they put on it. If it doesn't hold the vacuum, they won't re-gas it.

norseman · Wednesday at 9:26 PM

My old 5 series re-gassed today & was shocked at the price.
Apparently freon has doubled in price & unfortunately the car needs a lot of it ie 1250g.

Despite no indications of a leak it needs gassing pretty much annually to be really efficient. I've considered a DIY job but there are conflicting opinions regarding safety & the gas is going to be expensive anyway.

jj4091 · Thursday at 5:59 AM

norseman said:
. I've considered a DIY job but there are conflicting opinions regarding safety & the gas is going to be expensive anyway.

Been quoted £72 so not really worth diy

norseman · Thursday at 8:20 AM

jj4091 said:
Been quoted £72 so not really worth diy

In that case I totally agree, sounds like a very reasonable figure, but that's the sort of price I paid for my car back in 2021.
I'd be interested to know how much gas your car takes (injected) Should be shown on the readout slip the machine prints off.

Mottie · Thursday at 8:37 AM

norseman said:
I'd be interested to know how much gas your car takes (injected) Should be shown on the readout slip the machine prints off.

It’s normally on a plate on the bonnet slam panel.

norseman · Thursday at 9:17 AM

Mottie said:
It’s normally on a plate on the bonnet slam panel.

Thanks for that, I've never noticed such a plate but will look for it next time the bonnet is opened.
The figure of 1250g injected into my BM yesterday is shown on the printout from the machine.

Avocet · Thursday at 11:54 AM

norseman said:
Thanks for that, I've never noticed such a plate but will look for it next time the bonnet is opened.
The figure of 1250g injected into my BM yesterday is shown on the printout from the machine.

More often a sticker these days. It should have "R134a" on it, for a car of that age, and then the weight of gas in the system. They've all been on a new refrigerant with a vastly lower global warming potential than R134a for about 10 years now though. (R1234YF).

fixitflav · Sunday at 2:41 PM

Avocet said:
They've all been on a new refrigerant with a vastly lower global warming potential than R134a for about 10 years now though. (R1234YF).

I could be wrong, but I thought refrigerants were bad due to damaging the ozone layer, not for causing global warming.

Avocet · 2026-07-20T01:09:35+0100

fixitflav said:
I could be wrong, but I thought refrigerants were bad due to damaging the ozone layer, not for causing global warming.

You're right! The (even older) R12 refrigerant was indeed a vicious ozone depleter and that was the reason it was banned in the early 1990s. It also had the nasty habit of turning to mustard gas if it came into contact with a fire!

However, its replacement, R134a, was a terrible greenhouse gas. If you allocated an arbitrary value of global warming potential of "1" to CO2, R134a has a global warming potential of just under 1500! It was that which was the main driver for the development of the current automotive refrigerant R1234yf - which has a global warming potential of about 4. Unfortunately, the patent is held by a DuPont spin-off company and they've got the car industry by the short and curlies. Nothing else will meet the EU Commission's global warming potential requirements, so the industry has to pay whatever DuPont wants - which is why it's more expensive to get a re-gas.

Koolpc · 2026-07-20T06:48:56+0100

Whenever I got my Aircon on I find the car sluggish to accelerate at low speed. Turn the Aircon off, it's fine. Does that mean air con unit failing?

Burnerman · 2026-07-20T07:15:57+0100

It could mean that the compressor has become stiff to turn, for one reason or another.
Try the same test with the engine on tick over, then switch the A/C on......does the engine slow up a bit?
John

2005 Rover 75 Air-con

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