Can I work on the Air Conditioning System?

[Bahnsturmer]

I am slowly working through the issues with my W210 E320CDI. I still have to sort rusty brake lines, one of the rear door locks (I think an actuator problem) and the air conditioning system. The EC light cannot be switched off and there is no cooling. The history file indicates that the aircon compressor pump is faulty, but I could not find any record of it having been replaced.

My question is: Can I do any work on the aircon such as replacing the compressor without damaging the environment through the escape of harmful gas damaging the ozone layer, or should this always be done by a professional?

 

[mioba]

I would say given the environmental impact id use a pro at least to remove any gas. That way you could work on the compressor yourself to keep costs down and then have it refilled at a pro.

 

[LostKiwi]

Frankly given it should be professionally emptied and refilled you may as well have a garage do the lot. That said if it's all leaked out anyway then do what you like

I had my local garage do the lot with my old E240 and it was £300 labour (I provided the compressor) including emptying and regas.

Given yours is an I6 engine and not a V6 it should be easier to gain access so a bit cheaper.

If it's been leaking a while it will probably need a new drier as well.

 

[Bahnsturmer]

@mioba & @LostKiwi: thanks to both of you for your helpful responses.

I would like to keep the cost down. Is there a DIY way of finding out if there any gas left in the system? If the pressure in the system equals 0 there shouldn’t be any gas left in the system?

 

[LostKiwi]

Correct.
Even if there is the volume will be low.

 

[Mr Greedy]

The aircon gas pressure can be tested easily in two ways. A live data scan on iCarsoft should give you a pressure readout for the aircon system. If zero, it should probably be zero (but don't rule out a faulty pressure switch and actually therefore no leaks to the system).

A quick check is to take the cap off the fill line, and give the Schrader valve a quick press with a screwdriver tip or pen lid and see if there is any gas escaping. If there is, it needs degassing professionally.

Once empty, you can work on the system yourself.

When I did this using an aircon independent, they weighed the gas out, and charged me correspondingly less for gas on refill. Something like £60 all in for degas and regas.

If it was already completely empty, that indicates a serious leak, and moisture has likely entered the system.

You might need to replace the radiator with combined dryer (dryer tube down one side) if you don't have a separate dryer canister on your vehicle. A parts catalogue diagram would show this.

You could do a VIN check on e.g. Mahle website or Valeo and see if the spares list a rad with integrated dryer, or list a dryer separately.

 

[Bahnsturmer]

Thanks Mr Greedy!

 

[mattkh]

If it's been leaking a while it will probably need a new drier as well.

Is that because of a) or b):

a. It has taken say 5 yrs to leak, hence due for a change anyway
b. As it has been leaking, it is more likely to have sucked in moisture from the atmosphere

 

[LostKiwi]

B.