Is it true? and can it be?
 

Greetings all..my partner has been told by her garage that aircons are expected to lose upto 35% of gas each year as a norm...anyone know if this is true please?...just sounds odd to me...

and can it be...my 75 doesnt have a central plenum drain?!
I had thought months ago when i first bought the car that i checked as recommended but must have only checked the two outer ones...as this time i looked for the center one and ...its not there...the whole area where i expected it to be is completely dry and looks as if it never saw water. What there is, is a part of a wiring loom i guess encased in a corrugated plastic that disapears downward and not far from it, a rubber plug [i think]. so no drain would ever have had a plug in it would it?
Go well all and thanks for a great site...
Mark

I would say that the A/C system loss is minimal each year. I do my own top-ups and have found when I hook up the pressure guage on my refill kit (Not sure if they are available in the UK) that there is literally no change year to year. I bought a new refill gas cylinder 3 years ago and haven't had the need to use it yet on either my ZT or MGF.
As for the drains, I believe that one of them was deleted as part of Project Drive but you should still find one in the plenum. I should think it would be easy enough to just knock out the plug and put a replacement drain tube in.

AC systems can lose gas over a year, I probably wouldn’t say 35% but the A/C system is definitely a serviceable system

. All vehicles built prior to 2017 used a gas known as R134a. this is what is used in any of the MG Rover vehicles, As of 2017 a new type of gas, HFO-1234yf, is required by law for all new vehicles. The new gas produces 98% fewer climate-damaging pollutants so is a great step forward for the motor industry, in protecting the climate.

When your vehicles air conditioning is charged up with gas, which over time dissipates from the system. Around 10% of the gas is lost each year preventing the air conditioning from performing to its full potential, therefore I would suggest that 35% is excessive.

Hope that helps
Mick

One of the upper plenum drains was discontinued on later cars but as far as I know there has always been two lower plenum drains. The upper ones are just under the bonnet near the back of the front wings the other two are below the scuttle panel one below the pollen filter and the other underneath the servo. the latter is only really accessible from under the car.

The key to the garage statement is in the wording "to lose up to". this statement means nothing as "up to" is zero to 35%. this makes it compatible with all above statements. I would expect minimal loss of up to 10%. (see what I did there :D )

My wife had a PT Cruiser. When you wiggled one of the AC pipes gently you could hear gas escape. The connector was in a spot that was very hard to get a wrench into so I never tightened it up but it must not have been affected by vibration as the system never needed recharging.
On re-reading this thread I think Stocktake nailed it with the garage using the term "up to". That's a B S marketing term meant to scare people into doing jobs that probably don't need doing.

Hi Mark, I'd say the 35% might have been an off-the-cuff remark. After all, that'd mean it'd be completely empty in 3 years which I'd find hard to believe, unless the system has an actual fault ?

Regarding the drain, have you removed the wipers and the black plastic plenum cover, then looked down inside the void ? Or are you looking in the engine bay ? The centre drain exits beneath the car (as does the one under the servo) so neither can be seen in the engine bay.....if that's where you're looking ? I'd be very intrigued if yours doesn't have it, as the panel pressings are generally standard on any mass produced car.

If you have the wipers & plenum off, I can nip down sometime & show you where it is / should be ? :}

Hi Paul, no i didnt take the wipers off just the panels beneath them...should i be taking wipers off?...ok will check that out...thanks ;)

Hi Mark,

The actual loss depends upon how much the air conditioning is used. If it's left off for most of year then expect to lose a significant amount of refrigerant. If it's used for a period every month then the loss should be minimal or even zero!

If your partner's system is cooling efficiently then there's no need to worry or do anything. :}

Simon