Mercedes W205 Cclass, is it bad to use aircon without enough refrigerant R134 or compressor oil ?

benzw205

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Mercedes W205 Cclass, is it bad to use aircon without enough refrigerant R134 or compressor oil ?

hello,

Do you know if it is bad to use aircon without enough refrigerant gas in the system ? Should I refill as soon as it's not cold anymore ? (until I fix it definitively)

Actually the problem seems to be the compressor oil ? will the compressor break if I use aircon with an evaporator leak for a while ?
I need to remove the dashboard to change the evaporator coil, has anybody done it before ? Any video / tutorial ?

Thank you so much for your help.





Thank you for your help.
 

monkeh

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Hi yes, it is bad for you the environment and the compressor, i wouldnt use it until fixed and would have windows open when driving. if there is a leak it air and moisture will get in which will corrode the compressor
 

MrGreedy

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Most systems operate on a pressure switch, which in effect detects refrigerant pressure. Too low, and the compressor is shut off.

Too little oil is not really detected. If you have a refrigerant leak, you will also have an oil leak. Refrigerant leaks lower down e.g. bottom of the condenser are worse as they tend to leak more oil. Unfortunately there is no way of knowing how much oil has leaked from an open (leaking) system. It will depend on the severity of the leak and for how long e.g
many re-gases will give more opportunity for oil to leak.

Low oil in the system will ruin the compressor.

When re-gassing, an experienced aircon specialist will need to take an educated guess on how much oil to add back. Little more than required is generally better, as you sacrifice a little cooling efficiency for greater likelihood of providing enough oil to protect the components and therefore system longevity.
 

markjay

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AFAIK, on regassing, the old gas is completely removed, and the new gas is mixed with a fixed quantity of oil as per the manufacturer's specifications for each system.
 

Petrol Pete

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If I read your post correctly.....

As others have said The A/C compressor will not run if the pressure is too low , for example if all the refrigerant has leaked out. The pressure sensor will take care of that.

You hint that you have a leaking evaporator and want to use the aircon until you get it fixed.

If you pressurise the system yourself with DIY refrigerant you might get the pressure high enough for the compressor to start up but you will be running with little or no oil in the system = not good for the compressor.

You can buy various A/C 'stop leak' additives , I have no experience of using them but it might be worth a try (after you have done your own research) as removing the evaporator is a big job.

As said , if there is leak whatever you put in will come out, which is not good for the environment or those in the car if its leaking from the evaporator.
 

markjay

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In previous years some national chains offered complete regas for under £50 (probably on the premise once they get the customer through the door they'll try and upscale brakes and tyres etc), not sure if these are currently available though. Similarly, there where also Groupon coupons available for cheap regas at national chains, it was £35 I think.
 
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benzw205

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Thanks to all ! Not in UK or in EU.

Has anybody tried the DIY refrigerant spray + fix leak ?

Any famous brand ? Absolutely no risk to try before I pay someone to remove the dashboard and change the evaporator ?
 

MrGreedy

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Evaporator leaks are uncommon. Condenser leaks are most common, followed by a leak around the seal on the compressor shaft.

Are you sure it's the evaporator?
 
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benzw205

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Evaporator leaks are uncommon. Condenser leaks are most common, followed by a leak around the seal on the compressor shaft.

Are you sure it's the evaporator?


Sniffer found gaz when put through the air vent on the dashboard, so I guess the problem is evaporator ? Anyway it seems that the dashboard has to be removed.

I follow some AC specialists on facebook and they post daily photos and videos of evaporators they change on recent Benz, BMW, Porsche, etc... so it seems that the problem is quite common.
 

Martin 1

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This is important, before we offer you advice, where are you ? You mention R164, illegal in the UK.
 

MrGreedy

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Sniffer found gaz when put through the air vent on the dashboard, so I guess the problem is evaporator ? Anyway it seems that the dashboard has to be removed.

I follow some AC specialists on facebook and they post daily photos and videos of evaporators they change on recent Benz, BMW, Porsche, etc... so it seems that the problem is quite common.
Ah, if a sniffer has been used that could indicate evaporator.


To clarify, when I said uncommon, I simply meant in comparison to condenser and compressor shaft seal.
Evaporators do of course fail, but at much lower rates.
 

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