Air Conditioning Regas questions?

Goudy

Same as in the main part of this thread.
Check the belt first.

The air con electrical circuit is linked to the rest of the car's brain, so turning it on within the car will inhibit the stop/start system even if the air con doesn't actually work.
The car's brain just knows the air con has been activated so it keeps the engine running.

With the engine running and the air con off, the belt will just drive the air con compressor pulley and not the air con compressor.

Switch the air con on (climate set to below ambient temp), the electro magnetic clutch on the compressor pulley should engage so the belt and pulley actually turns the compressor rather than just the pulley.
You usually hear a faint clunk as it engages.

There is a pressure sensor on the system and if pressure inside the system is too low, it won't engage the electro magnetic clutch.

Of course other things cause the same problem, perhaps the electro magnetic clutch has failed, but after checking the belt, a check of the gas pressure is perhaps the next place to look.

If it's low/empty, they should try and recover what is left in there by creating a vacuum within the system.
This vacuum will also help boil off any moisture in there.

If it can't pull and hold a vacuum, it has a leak somewhere. So pointless to regas it until the leak is fixed.

If it pulls and holds a vacuum it's okay to regas and it should then work unless there's another problem somewhere, but you won't know until you get to that point.
You just can't tell if everything else is working until it's holding gas.

Belenus

Thanks everyone for your comments and suggestions.

I took it to my usual service place and they checked it and regassed it so I now have working air con again.

No faults other than lack of gas detected.

They gave me a print out from the machine.

Gas recovered 410 g
Oil recovered  32 ml
Vacuum 25 minutes
Oil injected 32 ml
Tracer injected 11 ml
Gas injected 550 g

They suggested that the air con should be serviced every two years. 

As far as I can recall my car's air con had not been serviced in ten years. It isn't mentioned on any of my service check lists etc.

Have I been lucky to get to ten years without a service?

Mildly_Miffed

Gas out - 410g
Gas required - 550g
So difference - 140g, or +34% over before, 25% of required.

Just goes to show how little a difference is required to trip the pressure switch...

Goudy

Air con systems don't like not being used.
The oil in your print out is a lubricant.
As well as lubricating the system, it helps keep all the seals pliable so they don't dry out and become brittle and leak.

Apart from re-gassing and re-lubricating the air con system as part of a service, the air con system has a dryer/filter.
A container full of desiccant that traps moisture and filters out debris from the refrigerant.
As you can imagine, moisture in the system will cause corrosion and the compressor has metal on metal moving parts that can create debris (more so if there's a shortage of lubricant).

The dryer/filter should be changed every few years or if the system has been opened in the case of a repair.

You may or may not be lucky.
They have put a tracer in the system.
This is a fluorescent dye that shows up under a UV light if it leaks out.
So they might be expecting you back if the system leaks again sooner rather than later.

facade

Belenus said:

Thanks everyone for your comments and suggestions.

I took it to my usual service place and they checked it and regassed it so I now have working air con again.

No faults other than lack of gas detected.

They gave me a print out from the machine.

Gas recovered 410 g
Oil recovered  32 ml
Vacuum 25 minutes
Oil injected 32 ml
Tracer injected 11 ml
Gas injected 550 g

They suggested that the air con should be serviced every two years. 

As far as I can recall my car's air con had not been serviced in ten years. It isn't mentioned on any of my service check lists etc.

Have I been lucky to get to ten years without a service?

If it uses R134a (possible in 2015) yes, 10 years is pushing it even with regular use.

If it uses R1234yf, absolutely YES!  3 years is pushing it for R1234yf, the capacities are smaller and it leaches out faster.

I had my R1234yf re-gassed at the MOT in April, it needed 160g of gas out of a capacity of 440g so it was near enough down to 2/3 of the gas.

It was still working but wasn't getting as cold as I wanted, and it was 3 years since the last re-gas.

So they are correct that it needs topping up around every 2 years, mine probably spent the last six months running a lot more than it should, accelerating wear on the pump.

Belenus

Goudy said:

Air con systems don't like not being used.
The oil in your print out is a lubricant.
As well as lubricating the system, it helps keep all the seals pliable so they don't dry out and become brittle and leak.

I use mine regularly, even in winter. Partly to stop the seals drying out and partly because it helps to dehumidify the air and clear the windscreen of condensation.

Belenus

facade said:

Belenus said:

Thanks everyone for your comments and suggestions.

I took it to my usual service place and they checked it and regassed it so I now have working air con again.

No faults other than lack of gas detected.

They gave me a print out from the machine.

Gas recovered 410 g
Oil recovered  32 ml
Vacuum 25 minutes
Oil injected 32 ml
Tracer injected 11 ml
Gas injected 550 g

They suggested that the air con should be serviced every two years. 

As far as I can recall my car's air con had not been serviced in ten years. It isn't mentioned on any of my service check lists etc.

Have I been lucky to get to ten years without a service?

If it uses R134a (possible in 2015) yes, 10 years is pushing it even with regular use.

If it uses R1234yf, absolutely YES!  3 years is pushing it for R1234yf, the capacities are smaller and it leaches out faster.

I had my R1234yf re-gassed at the MOT in April, it needed 160g of gas out of a capacity of 440g so it was near enough down to 2/3 of the gas.

It was still working but wasn't getting as cold as I wanted, and it was 3 years since the last re-gas.

So they are correct that it needs topping up around every 2 years, mine probably spent the last six months running a lot more than it should, accelerating wear on the pump.

My 2015 car uses R134a gas.

The regassing service cost me £84. I could have paid £59 at Formula One but they could not fit me in at a convenient time whereas my usual service place could.

I also felt more comfortable going to a place that I have used before and that has an excellent local reputation.

Eames Motor Repairs in Terminus Road, Chichester if anyone is local and is looking for a reliable service place.

QrizB

Mildly_Miffed said:

Gas out - 410g
Gas required - 550g
So difference - 140g, or +34% over before, 25% of required.

The fact it still has 75% of the gas in the system suggests to me that there isn't a gross leak. OP could be good for another decade.

rca779

I had my Jag air con re-gassed this weekend and touch wood it seems to have fixed the issue. I used Kwik fit, but managed to negotiate a deal as I had seen a 25% discount at ProTyres. So I have to use the R1234yf gas and I got it done for £90