Air Con Gone Again

[The Cav]

For the 3rd yr in a row it looks like I will have to take my 2.2 D4D T Spirit for a re-gas

It must have a tiny leak that over the summer and winter months allows the A/C gas to escape

right now it is not very good despite having a re-gas last summer and the summer before

When I 1st had it re-gassed the guy said it was completely empty of gas and therefore must have a leak

But when he checked it...It held its pressure...then last summer it was not vey good so i took it to another guy who said it wasn't completely empty of gas and re gassed the system saying it would be OK as it wasn't showing a loss of pressure there and then...well now its not working properly again ...yes it does cool down but not very well...so obviously there is a slow leak somewhere....

Am i right in thinking that the compressor wont work if there is no gas pressure present in the system...only my compressor still raises the engine revs..When the A/C is turned on (from 800 to 1000 rpm)..I was lead to believe there is a pressure switch on the system which controls the compressor ..no gas ..no working compressor

TBH I don't mind paying the £50 every year to have it re-gassed if i have to ...but it would be nicer if i didn't have to ...if it would hold the refrigerant in the A/C System

BTW has anyone else had this type of problem?...Can any one suggest where the leak my be??

Any help would be greatly Appreciated

cheers

[Phil White]

I am a mechanic myself and have dealt with aircon for the past four years.

The compressor won't work with no gas in the system as there is a pressure switch in the pipework and that needs to see pressure for the clutch on the compressor to engage.

Did the garage put any leak tracer dye in with the lubricating oil when you had it regassed??

This will be detectable with a special lamp but is not completely foolproof as not all the system is exposed, for example the evaporator behind the facia might be leaking and it's impossible to see behind there and if the leak is so slight the sniffer might no pick it up either.

The other alternative is to charge the system with nitrogen gas under high pressure and use soapy water from a standard spray bottle and where ever the leak is it will form bubbles, a bit like tracing a tyre puncture.

It might be worth asking if they did any of the things i have mentioned and also aircon should be used all year round as it will give a longer service life as it may be something as simple as an O ring seal on any of the fittings that has contracted or deteriorated allowing the gas to escape.

TBH the most common area of leakage is the condenser unit which looks like the radiator and is often situated in front of the radiator and can leak due to weathering or stone chips etc..

Hope i have been of some help for you.

[Phil White]

I am a mechanic myself and have dealt with aircon for the past four years.

The compressor won't work with no gas in the system as there is a pressure switch in the pipework and that needs to see pressure for the clutch on the compressor to engage.

Did the garage put any leak tracer dye in with the lubricating oil when you had it regassed??

This will be detectable with a special lamp but is not completely foolproof as not all the system is exposed, for example the evaporator behing the facia might be leaking and it's impossible to see behind there and if the leak is so slight the sniffer might no pick it up either.

The other alternative is to charge the system with nitrogen gas under high pressure and use soapy water from a standard spray bottle and where ever the leak is it will form bubbles, a bit like tracing a tyre puncture.

It might be worth asking if they did any of the things i have mentioned and also aircon should be used all year round as it will give a longer service life as it may be something as simple as an O ring seal on any of the fittings that has contracted or deteriorated allowing the gas to escape.

TBH the most common area of leakage is the condenser unit which looks like the radiator and is often situated in front of the radiator and can leak due to weathering or stone chips etc..

Hope i have been of some help for you.

[Roker]

The compressor is the variable vane type and does not engage with a clutch, if there is no refigerant and hence oil in the system, it will damage the compressor. Mine had a leak on the HP tube on a bend below the Battery, the 90 deg bend was too tight and stressed the metal causing a hairline crack. If this is the place you will see oil on the inside of the engine under covers