I can confirm after changing my water pump and seeing a label on top of the A/C compressor that the low side should be ~16.7 Bar and the high side should be ~35.3 Bar

Here's the label values are in MPa (Mega pascals) 1 MPa = 10 Bar:

Thanks for the info Ollie........

Just a little warning, Got my refill kit today, it has a filling gauge with a green zone on it ranging 25-40 PSI this is a lot less than the values stated on the A/C pump, I can only assume these values are for maximums or when the system is in use?

Just so people don't try to over pressure it!

Indeed. You should really fill by weight of gas, not pressure - although many seem to get away with it.

I think you're right that the pressures on the pump are absolute maximum for the pump itself, not the overall system.

Well just in case anyone wants to see these were my results:

You can only put the refill on one pipe but its the large one:

Click image to enlarge

There will be pressure in there quite quickly. The R134a has a vapour pressure that depends only on temperature, so any liquid r134a in there at all will produce the same pressure if the pump is not running.

If you're trying to fill the system you will need to start the engine & run the compressor, then fill from there. The gauge/fill is connected to the low side i.e. the compressor inlet and the pressure is meant to be read with the compressor running.

Remember that the IID tool is reporting the high side pressure, so when the compressor is running this will be (a lot) higher than the gauge.

Having said that you really need to vacuum out first, especially if the pipes have anything other than R134a in them (e.g. they have been open to the atmosphere)....

However were not going by the book here are we?!?

I got a refill kit yesterday to do the wifes car and it states on the instructions that if it shows 0psi when you first put it on to NOT ATTEMPT TO REFILL WITH REFRIGERANT, CONSULT A PROFESSIONAL!

Guess you missed that bit on your instructions pal?


Not sure why it states that though as the stuff says it seals pinhole leaks and seal leaks but nothing larger than that, well surely after a year of having a pin hole or seal leak then you'd lose all gas anyway wouldn't you?

Are you meant to check it on a daily basis, oops I've lost 1psi I'll just top it back up again.

Give it a few checks over the coming days and let us know mate as my wife was very sad that I couldn't cool her car off at the time but if yours stays at a solid level then I'll give hers a go anyway. Dan

2002 Zambezi Silver

Men And Motors RR Quote - It's like having wheels fitted to your living room!

Thanks for all the info guys, I've been busy lately but hope to get around to topping it up tonight.

There's lots more info on the forum for anyone in the same position.

http://www.fullfatrr.com/forum/topic37273.html

I thought I'd give it a try as I don't know how long its not been working for (only had the car 6 months and had so many problems its unreal, I am assuming now though that it has a rather big leak somewhere as it is now back at 0, looks like the most likely culprit could be the condenser going from other posts on the forum? not intending on keeping the car so It was a last ditch attempt to get the A/C working again!

luckily I didn't use much of the can and used the rest of it on my other car which was low but definitely not leaking!

Not good news Ollie, hope you get is sorted.

I had a go at this last night too, €34.49 for the recharge can and €17.24 for the gauge and trigger, (I have a trade card for Halfords).

Popped the gauge on and there was 10psi in the low pressure side and reading 5.666 with the IID tool on the high pressure side, charged in about 10 second bursts monitoring the readings, clutch engaged around 10 bar on the HP side and brought the LP side up to about 25 psi and the HP to about 17 bar and nice and cold again.

The IID tool is also showing the compressor clutch is now switching on and off when the a/c is switched on and off.

Had a very quick look this morning and the IID tool is showing the HP side is now closer to 20bar so I'll keep and eye on that over the next few days but fingers crossed it's sorted.

I guess reading the thread and comments back again, if your LP side is reading 0 psi at the start then there's obviously a chance you have a leak, I was lucky, I hope, in that my LP side was reading about 10 psi from the start and only needed to be topped up, it's 11 years old and quite possible never touched before (not the highest of priorities with the weather in Ireland ) so one would assume there would be a drop in that time.

Well now I have the engine running again I thought I'd just quickly prove the system worked by gassing it up enough to get it to run, to my relief it all kicked in perfectly, It didn't seem to loose pressure (on the high side using IID) when it was running and would sit at ~14.3 Bar turn it off and it would slowly drop down to around 9 Bar but kick in again if the button was pressed, I didn't get any cooling as there can't have been enough pressure, but when sat inside noticed a prominent 'bubbling/hissing noise' coming from the centre of the dash, is it possible that it could be a evaporator leak? had a look at what I can see of the condenser and it looks in pretty good condition, the evaporator is also a bit cheaper than the condenser!