Air conditioning problem

[MBnewbie123]

Hi,

Assistance with the solving the problem detailed below would be appreciated:

When the air conditioning is on - no cold air is being blown into the cabin. I brought the car to Halfords to see if it needed re-gassed, but the device that was used to determine if the gas level was low had the needle at “Warning”. I appreciate this means that I should get the car looked at by a mechanic, but, what is normally the cause of this? Is there anything I can do to fix it without needing to take it to a mechanic? My car is a W204.

Kind regards.

 

[Blobcat]

The condenser corrodes and the gas leaks in a lot of cases of AC failure.

Find an experienced AC specialist (not someone who’s had 10 mins training on the AC machine) and they’ll be able to diagnose the issue and what it will need to fix it.

 

[alexanderfoti]

+1, pressure can only tell you so much (and wont have a low pressure "warning" only high!)

 

[MBnewbie123]

The condenser corrodes and the gas leaks in a lot of cases of AC failure.

Find an experienced AC specialist (not someone who’s had 10 mins training on the AC machine) and they’ll be able to diagnose the issue and what it will need to fix it.

Thanks, Blobcat. Forgive me if this is a stupid question, but, if there is a leak, surely the gas would have leaked out and the gauge on the gas canister (being used to re-gas the AC system) would show that the pressure was low?

 

[Blobcat]

Thanks, Blobcat. Forgive me if this is a stupid question, but, if there is a leak, surely the gas would have leaked out and the gauge on the gas canister (being used to re-gas the AC system) would show that the pressure was low?

I don't know what was used, normally they hold a vacuum on the system for a set period before adding new gas. If it holds a vacuum they'll re-gas it for you. Sometimes this doesn't highlight a leak as the vacuum can pull the leak closed and the gas will leak out again in a short period of time. A dye can also be added which if it leaks out can be seen with a UV light.

 

[V6Matty]

If the system has shutdown for no gas to protect itself it may be that pressure shows high as it’s essentially locked out, you may need to diagnostic and check running and then see live values of the system

 

[MBnewbie123]

I don't know what was used, normally they hold a vacuum on the system for a set period before adding new gas. If it holds a vacuum they'll re-gas it for you. Sometimes this doesn't highlight a leak as the vacuum can pull the leak closed and the gas will leak out again in a short period of time. A dye can also be added which if it leaks out can be seen with a UV light.

They used this - https://www.halfords.com/motoring/e...ional-quick-charge-gun-with-gauge-626284.html

If you look at the gauge, it shows at the right-hand side of it a large section in red, which is what states "WARNING". Is it possible that there is a blockage?

 

[V6Matty]

They used this - https://www.halfords.com/motoring/e...ional-quick-charge-gun-with-gauge-626284.html

If you look at the gauge, it shows at the right-hand side of it a large section in red, which is what states "WARNING". Is it possible that there is a blockage?

Yes as above

 

[MBnewbie123]

I got it fixed. There was a wire disconnected. I should have asked what the wire was for, but it seems it was inadvertently or advertently disconnected when someone was replacing a cabin air filter. So, there was nothing wrong with the air con system. Thanks for the help though.

 

[MBnewbie123]

Thanks to everyone for the replies. Much appreciated.

 

[rifiki]

And when you do get the AC fixed use it all the time you won't have any more problems.