R231 Air conditioning mystery

[SL63 Mark]

Now the hot weather has arrived, my air conditioning has stopped working.

MB say that the car can only by filled with R1234YF gas by a licensed MB dealership at a cost of £350. Only two or three dealers can do this outside London. On top of that diagnostics will be required to locate the leak. (if any). This gas is unique to the S class and SL.

When I bought the car the aircon was not working, so the vendor re-gassed it, I am assuming they used "normal" gas, hence possibly why it has leaked out again.

Has anybody heard of this "special" gas, or is this all just hot air ?

 

[Uncle Benz]

It’s not that special. Most cars from 2016 have this gas. I have the machine, so it’s not as difficult as they are telling you. I charge £95 for an R1234yf regas

 

[Uncle Benz]

My machine…

 

[AndySlade]

Now the hot weather has arrived, my air conditioning has stopped working.

MB say that the car can only by filled with R1234YF gas by a licensed MB dealership at a cost of £350. Only two or three dealers can do this outside London. On top of that diagnostics will be required to locate the leak. (if any). This gas is unique to the S class and SL.

When I bought the car the aircon was not working, so the vendor re-gassed it, I am assuming they used "normal" gas, hence possibly why it has leaked out again.

Has anybody heard of this "special" gas, or is this all just hot air ?

Avoid MB dealership, I used a mobile Vehicle Air-Con specialist local to me I found in an on-line search. He can refill with any of the available gases. As that’s his prime source of work. Have a google and see if one is near you. I am sure plenty of the MB Indies would be able to do similar.

 

[SL63 Mark]

Avoid MB dealership, I used a mobile Vehicle Air-Con specialist local to me I found in an on-line search. He can refill with any of the available gases. As that’s his prime source of work. Have a google and see if one is near you. I am sure plenty of the MB Indies would be able to do similar.

That is a really good idea, that is why I like this forum. Thankyou.

 

[SL63 Mark]

Hmm - I have been doing some research (see below) apologies for the long post. (info courtesy of www.top-refrigerants.com)

Yes R1234yf Freon gas can be replaced by R134a, the newer systems were designed with this in mind so no, there will be no damage to the compressor but doing so is illegal.

Retrofitting r-1234yf mobile air conditioning systems is prohibited​

Note: The information in this article is the current overview as collected by Top-refrigerants.com from industry and regulatory sources. It is not intended to provide all possible issues covering any system modifications and operation or servicing of production R-1234yf mobile air conditioning systems.

What happens if you put the wrong refrigerant in your car?​

You cannot mix refrigerant types, and putting the wrong refrigerant in your car will cause damage to the air conditioning system! If you’re not sure which kind of refrigerant your vehicle takes, DIY A/C charging may not be for you.

Are r134a and R1234yf fittings the same?​

Vehicles with R-1234yf have different service fittings than R-134a vehicles to prevent cross-contamination with different refrigerants. Also, it’s illegal to put R-134a or any other refrigerant into a car originally equipped with R-1234yf. In fact, using any refrigerant other than R-1234yf in a R-1234yf system may constitute emissions tampering if the manufacturer counts air conditioning credits (use of R-1234yf) towards light-duty, greenhouse gas (LD GHG) compliance. Many R-1234yf systems also use an internal heat exchanger (IHX) not commonly found on R-134a vehicles. The IHX is integral to the low-side system plumbing and improves cooling efficiency. Of course, like other A/C systems, R-1234yf systems will have a unique system label showing the refrigerant type, charge amount, oil type and more.

What happens if you mix R-134a and R1234yf?​

The expansion valve setting for R-1234yf refrigerant is different compared to R-134a. Changing from R-1234yf to R-134a refrigerant may result in a system with incorrect refrigerant flow and heat exchanger mal-distribution which may cause a loss of cooling performance or durability concerns.
The TXV setting is also different when an Internal Heat Exchanger (IHX) is used, which is common in R-1234yf MAC systems. This may mean that suction line pressure drop is increased, which might affect the setting for a pressure controlled compressor, resulting in poor cooling or evaporator core freezing.
This can be particularly damaging in the case of dual evaporator systems where the balance of front and rear expansion devices helps to avoid oil trapping in the rear evaporator.

Evaporator control​

Evaporator control settings are important both for maximum performance and reduced load requirements at cooler ambient. Depending upon the method of control for maximum cooling performance (pressure or temperature control), different settings may be required when changing the refrigerant.
Refrigerant pressure control of the compressor with either cycling compressors or variable displacement compressors is affected by the refrigerant used in the system. Systems that use air temperature sensing for controlling the evaporator may not be affected by changing from R-1234yf to R-134a.
R-1234yf systems that control freeze protection by pressure may encounter loss of cooling performance if charged with 100% R-134a. This is due to the requirement of R-134a to have a lower setting of 3.3 psig to achieve freeze protection at 32 F. This may result in a 4-degree F. (2.2C.) warmer outlet air temperature.
The mixing of R-134a with R-1234yf will change refrigerant pressure and may result in evaporator freeze-up on pressure control systems, reducing system airflow.

Can a Mercedes-Benz R-1234yf be converted to R-134a?​

You can convert an empty R-1234yf system to R-134a. Mercedes made this obvious when it raised objections to R-1234yf years ago and recalled European models with the refrigerant, recovered it from the vehicles’ systems and recharged them with R-134a.

 

[SL63 Mark]

It’s not that special. Most cars from 2016 have this gas. I have the machine, so it’s not as difficult as they are telling you. I charge £95 for an R1234yf regas

Thanks Uncle Benz, I will go the independent route. MB want £350 for the re-gas, plus £195 for investigation/diagnostics, then probably £,000s for fixing it.

Apparently only MB Epsom, Poole and Southampton can do it in these parts.

 

[rifiki]

Can't help which type of gas
It's the old storey with vehicle ACs, use or loose it.
I have the AC on all the time summer and winter.
Done nothing to AC on my 05 CLK.

 

[peterws1957]

Thanks Uncle Benz, I will go the independent route. MB want £350 for the re-gas, plus £195 for investigation/diagnostics, then probably £,000s for fixing it.

Apparently only MB Epsom, Poole and Southampton can do it in these parts.

How can they possibly justify £350 for a re gas. Extortionate even for the nonsense prices that dealers charge.

 

[Larkone]

How can they possibly justify £350 for a re gas. Extortionate even for the nonsense prices that dealers charge.

All those shiny suits, glass showrooms and free coffee have to be paid for somehow.

 

[Srdl]

Thanks Uncle Benz, I will go the independent route. MB want £350 for the re-gas, plus £195 for investigation/diagnostics, then probably £,000s for fixing it.

Apparently only MB Epsom, Poole and Southampton can do it in these parts.

ATS advertise a fixed price of £125

Air Conditioning Regas R1234YF - Book Online | ATS Euromaster

Book your air conditioning regas using R1234YF gas online now at a ATS Euromaster near you

www.atseuromaster.co.uk

 

[EmilysDad]

ATS advertise a fixed price of £125
....

I recently had my Smart 451 re-gassed for £59 at a local Formula 1 https://www.f1autocentres.co.uk/ The system was already working to a degree, just low on gas, so no idea how competent they would have been in sorting any faults.

 

[daibevan]

ATS with a groupon voucher do R1234YF for £93.

 

[rorywquin]

Can't help which type of gas
It's the old storey with vehicle ACs, use or loose it.
I have the AC on all the time summer and winter.
Done nothing to AC on my 05 CLK.

Ditto - apparently the seals dry out if not regularly used.

 

[ajlsl600]

Thanks Uncle Benz, I will go the independent route. MB want £350 for the re-gas, plus £195 for investigation/diagnostics, then probably £,000s for fixing it.

Apparently only MB Epsom, Poole and Southampton can do it in these parts.

Basically they don't want Yr custom, remember that when ur looking pts n service. Only interested in people who don't care about the costs.

 

[Botus]

no - they charge 280 an hour and make you pre book the waiting area and pay for a coffee these days

if you go to slaves r us, they'll charge less, maybe 85 an hour or for some things where the machine does the work, and then animals r us, using super slaves on 14.50 an hour might do it for 60

the first garage ought to do it thoroughly and get it right, (and might even flash the systems software with an update - it probably needs) - a good second one, might do it OK but will never know about the software, and animals r us, might forget the oil in and push the wrong amout of gas in there - whilst another customer takes the paint of the corner of your rear bumper

 

[Uncle Benz]

ATS with a groupon voucher do R1234YF for £93.

Wow! Those bastards have undercut me again

 

[Uncle Benz]

Fwiw I don’t ask to see a voucher

 

[daibevan]

If I lived near you I'd rather come to you and bu@@er the extra couple of quid.

 

[SL63 Mark]

Same here, car is booked in at MBS Southampton, let's hope they can fix it.