W210 (E320) Air-Con

[shirleydrive]

Popped into Kwik-Fit today to ask whether their offer stating no charge if Temperature at vent does not reduce by at least 10% after re-gas. The guy was was a little hesitant then went on to say that their thermometer was broken! I said , no problem, we can monitor the evaporator temperature on the climate control diagnostics. He then went on to say that after re-gas this model of Mercedes would need to go back to the main dealer to be reset. Told him I didn't think this was the case. AM I RIGHT?
My problem is that there is absolutely no cooling effect from the air-con. Checked parameters via climate control display and found evap. temp. Sensor not changing from 50 Deg C. Also gas pressure (engine not running) at 3 Bar. Anyone tell me what static pressure should be - 3 Bar seems a bit low so suspect low on gas. Replaced evaporator temp sensor. Now reading same as L/H and R/H core temp. Am going back to KwikFit tomorrow for re-gas. Will update
R


Replaced evaporator temp.

 

[davidjpowell]

If you have the digital display you can reset it with the buttons. I'm not sure how I did it, but I managed to do mine in this way when Kwik Fit could not.

 

[shirleydrive]

Thanks for that David, I thought that was the case.

Just in case anyone is interested, instead of buying new sensor, I replaced the thermister at a cost of around 50P. Bought 10 in the States last week so have some spares. If anyone wants one let me know.
Mike

 

[BlackC55]

I expect the condensor is leaking. They are common for it.

 

[BAZZER1]

Thanks for that David, I thought that was the case.

Just in case anyone is interested, instead of buying new sensor, I replaced the thermister at a cost of around 50P. Bought 10 in the States last week so have some spares. If anyone wants one let me know.
Mike

Hi
Interesting to know about the Thermister, not being a air con expert, what is this and where is it fitted, I would be interested to have one if you any spare please
Thanks
BAZZER1

 

[shirleydrive]

Hi ,
The link below will take you to a PDF document explaining all you need to know about evaporator sensor repair. It lists a UK stockist for the thermister (Farnell). Unfortunately they have minimum order of £20. I happened to be in the US last week and was able to purchase thermister for 84 cents so bought 10.

http://www.benzworld.org/forums/att...failed-evaporator-evap-temp-sensor-repair.pdf
If you r,require any further info email me at [email protected]

 

[shirleydrive]

Had the air-con re-gassed today at Kwik Fit. Very pleased with the results. Printout stated 0.278Kg of gas (R134A) removed from system then 1 Kg added plus some compressor oil. Their machine initially vac ed the system down then left for 20 minutes to check for leaks.
Checked temperature at vents with infrared thermometer at registered 5 - 6 Deg C. Called up evaporator temperature and was reading 1- 2 Deg C. Cost - £49 and took just over an hour. Hopefully the system will continue to hold pressure - time will tell. At least it proves all the system components operate correctly.
Mike