safe to disconnect aircon (series 2 V12)

[foxy99]

When I bought my '74 Daimler Double Six VDP as a non runner
many moons ago the seller warned my several times not to
accidentally disconnect the large hose that runs to the
compressor, if I was working on the engine.

I didn't pay much attention at the time but now I am considering lifting the engine out to tidy up the engine bay. The hose would therefore need to be disconnected.

What are the issues, if any, with this?

[DWDarkWheels]

Safety is the main concern. The refrigerant gas turns to very cold liquid when released. If you release it in an unsafe manner and get splashed, it'll freeze/burn your skin.

Usually there's a connection in the system for proper bleeding of the gas, used by the professionals when they discharge the system.

There's also the environmental aspect of releasing what I expect are CFCs into the atmosphere.

[guslopez]

Jan 30, 2012 12:48:45 GMT DWDarkWheels said:

Safety is the main concern. The refrigerant gas turns to very cold liquid when released. If you release it in an unsafe manner and get splashed, it'll freeze/burn your skin.

Usually there's a connection in the system for proper bleeding of the gas, to be used by the professionals when they discharge the system.

There's also the enviromental aspect of releasing what I expect are CFCs into the atmosphere.

I confess I disconnected the system from my Omega donor. I disconnected the pipe and eased it open slightly, and left it to discharge the system, which took maybe 20 minutes or so.

Yes it's totally illegal. Gas has to be recovered.

[CR500Dom]

There is an "Unlimited Fine" for discharging refrigerant into the atmosphere......

don't do it

[SamR380]

Illegal to vent to atmosphere, but there are mobile air con companies who can work from their vans.

Being old, the gas could be quite nasty stuff. The law aside, it is a dangerous job to DIY.

[ax16vts]

you wont get burns off the gas, its the liquid that will burn if you get it on you.

It is illegal to vent cfc/hcfc refrigerants to atmosphere, however if you were to have a small leak on your system and lose the charge its hardly your fault is it. Not saying its legal, or morally correct but ive worked on plants were we've lost tons ( and yes, i mean literally) of r22 to atmosphere because of leaks so to be honest i cant see the kilo or less or refrigerant in your system making a big hole in the ozone layer.

The safest place to "have a leak" is on the suction pipe running to the compressor or the one running from the compressor to the condenser on the front of the car as thats where the refrigerant will be in its gas stage.

If you just crack the nut off, the hose will come off its seat and vent to atmosphere - don't remove the hose completely. Also, don't run the compressor as the oil is carried round the system in the gas and so you will be running it with reduced/no lubrication. When you recommission it you will need a new dryer unit which removes any water from the system, also itll need vaccing out and the gas recharging.

There is a bit more than that to it but if you take it somewhere to get the system recharged they should do all that for you.

[bigfella2]

Didn't Jeremy Clarkson and the Hamster do this to captain slows Rolls Royce to stop the air-con working in the India Top Gear special??

[stretch]

that they did but they get away with a lot things they we cant lol

[RobinJI]

I'm pretty sure the Passat I pulled the engine from for my mini had schrader fittings in the hoses for removing/adding gas. I know it's illegal to vent it to atmosphere, but would it be illegal to DIY vent it to another container? That'd be easy enough to do with schrader fittings surely?

[ax16vts]

you would still be venting refrigerant. first off the standing pressure, depending on the gas and the temperature will be 60-100 psi or more so your cintainer needs to hold that. Trouble is once the pressure has equalised in both containers there will still be a percentage of the charge left which you can only get out with a recovery unit. You also then need to get rid of the gas you removed, let alone the regulations you are flouting re unmarked containers and pressure vessel regs.

I could do it for you but its a long way to come, your better off having a "leak"...

[CIH]

Personally, I'd be incredibly surprised if it still held gas after all these years - unless it's recieved attention at some point within the last few years.

[foxy99]

Hi guys. Thanks for the input. All very interesting but its came to pass that you can access practically all the ancilliaries without removing the aircon system.

The Haynes manual suggests 'hanging it out of the way and avoiding straining the hoses' which sounded a bit dodgy but its worked just fine and has allowed me in to remove/check the radiator/water pump/air pump/PAS pump/oil cooler/fans and all the belts & wiring ;D.

The good news is that nothing needs replaced although they all needed a good clean and the water pump and air pump rotors needed a little persuasion to unstick. Both spinning freely now.

If I ever get the car running I can then take it to someone to check/revive the aircon.


busy front end



per Haynes manual condenser can be lifted out and placed on top of engine



once aircon and radiator are out of the way everything else is very accessible. piece of wood placed under condenser to stop it getting damaged on cylinder head