Mercedes W220 (S500, S430, S320) Air Conditioning (A/C) Service - full video

[@Mercedesdriver2012]

hello masood.the video is absolutely fantastic! the detail shots and explanations are excellent. Best regards from Germany .👍👍👍🔧🔧Michael.

[@masood-tv]

Thanks very much, Mercedesdriver2012.

[@mechris7973]

99 out of 100 times the valves at the high and low ports leak after a few years. Not changing these at this point is missing an opportunity to correct a leak that is always overlooked. It will even show that it holds a vacuum because the ports are closed off with the connectors when doing the vacuum so the valve leak does not show up.

[@masood-tv]

You are making a very good point. Thanks. I wish I had the correct Schrader valves to replace them. But, at the time, I didn't. However, I do own the adapters to replace them later if they leak without having to evacuate the freon again. I too would recommend to replace the valves as part of this job.

[@marijanmanevski4318]

Could you give more details how to change the system from R744 to R134a ?

[@AA79ER]

Masood, thank you for the response. my system was working great until the pulley and clutch broke off and damaged the pulley mount. Would this situation need a flush, 2005 115K.

[@masood-tv]

Well, it is hard to tell if nothing broke inside the compressor. I would say, yes, to be on the safe side and not to have to recharge.

[@SAYWUT]

What was the reason for replacing the expansion valve? Any specific symptoms? I have a w220 s500 where the high and low side are the exact same pressure.

[@masood-tv]

Hello, I replaced it because it wasn't for 23 years. The AC wasn't cooling like it used to. Even with a closed system like the AC, some refrigrant escapes over time. In 23 years, enough not to cool as before. I vacuumed the system because I wanted to charge the system with the exact MB specified amount of refrigrant. The expansion valve is very cheap, and the receuver drier should be replaced at least once every 10 years, in my opinion . But, definitely, if the expansion valve or any other AC component is replaced. I hope this answers your question.

[@Bizija123]

And?? What were the results of all this? What kind of temperatures were you getting at the vents? My 01 S430 cannot cool better than 60f at idle on a 95f day. Cools better when driving. I Even recharged after vacuum and still, that's coldest at idle. Pressures look fine. Should i replace the dryer and expansion valve to get better performance? Or is it time to replace the condenser after 23 years?

[@masood-tv]

Well - I got a 10 degree F improvement. In high 80's and 50% humidity, the inside vents read 35 to 36 degrees. When outside temp is in the high 90s with similiar humidity, I can get 42 to 45 degrees from center vents. After 23 years, if you have never replaced the receiver/drier and the expansion valve, replace those first. If not much better afterwards, then replace the compressor and condenser.

[@Bizija123]

@@masood-tv makes sense. Thank you for the response. I have to double check that all the fans are working as well.

[@masood-tv]

My pleasure. Absolutely. Check the fans first. I presumed you alreasy had. 60 degrees is unacceptable. It shouldn't go above 50.

[@javigee2020]

Hi masood i got a 2000 mercedes s500 and my ac completely dosnt work or heater what would you think the problem is i really dont wanna take it to a mercedes company cus they gonna charge a arm and a leg so i been tryna watch as much videos as possible to do it my self

[@masood-tv]

Hi, please elaborate. Does the blower turn on? Does the compressor turn? Does the radiator fan wirk? Does the system have enough refrigrant? You have to check everything methodically. I suggest you at least have it diagnosed.

[@SimonAndrews-d7x]

Hi , i have w220 fitting new air con compressor,i have flushed air con system by taking system apart etc.should be no oil in system now.new air con compressor has 120ml oil ,do i need to add any more oil to system?any advice woul be appreciated

[@masood-tv]

Hi, if all you are replacing is the compressor, you don't need to add more oil than that.

[@SimonAndrews-d7x]

Thanks for reply , I am also replacing the drier and I have dismantled and flushed all the pipes and evaporator so should add more oil than the 120 ml in compressor

[@masood-tv]

Yes, you do.

[@SimonAndrews-d7x]

@@masood-tv Thanks for your reply how much extra oil would you recommend?

[@masood-tv]

Hi You can add 10cc for the drier. May be another 3 to 5cc for flushing the evaporator and the lines.

[@AA79ER]

Masood when do you recommend flushing the system and how?

[@masood-tv]

Hi, the best occasion to flush would be after removing the expansion valve as you would have access to both inlet and outlet of the evaporator housing inside the dash. Of course, you must flish the lines and everything else if the compressor or the condensor have gone bad. As to the how of it, please search youtube. Perhaps, I would make a video when I do it next time.

[@AA79ER]

Masood, followed your procedures, after charging up first can of freon low pressure reads 110/high pressure 110 and clutch does not seem to engage, any suggestions? no codes

[@masood-tv]

Hi Edward, could you please elaborate. How was the AC performing before? Was the compressor/clutch working?

[@AA79ER]

@@masood-tv yes, the pulley and clutch disintegrated so I replaced the compressor because of shaft damage, and dryer. I found no debris in lines and compressor was still rotating smoothly. I vacuumed out the system after changing shraeder valves. At half can of freon started engine and ac, low pressure rose to 100 psi and high pressure to 100psi. compressor clutch fails to come on but fan does come on.

[@masood-tv]

I think your system is either overcharged or there is a blockage somewhere. Please click in the description on the Nissens link which explains the various pressure variances between the low and high sides.

[@AA79ER]

@@masood-tv I think we found the issue, the wire connection on the compressor. looks like a green single wire connecting to the red single compressor wire, but the connection won't click together and hold. Is this the correct connection. I can't find any other....

[@masood-tv]

It depends on the compressor. In some off brand ones, there is a single red wire and another ground wire that is connected to a nut on the compressor. That kinda makes sense, usually when both pressure numbers are the same, it is because of the compressor not working, but the numbers are usually close to the ambient temp. Besides, I had thought since you had replaced the unit, you must have first confirmed it was turning...good luck. Please let me know how it goes. It definitely needs a solid connection to work.

[@davidsyked9420]

Did you change the cabin filter

[@masood-tv]

Not this time, but do on a set schedule...

[@sukhbirbajwa6769]

Is there a shop who can do it for reasonable price in Bay Area , California?

[@masood-tv]

Hi Sukhbir Bajwa - I am sure there are plenty in the Bay area. However, I don't live there and could not tell you who charges a reasonable price. Please shop around.

[@davidsyked9420]

How did you know the expansion valve was bad

[@masood-tv]

Hi, I explain it starting at 12:50 minutes for the next 3 to 5 mins...

[@OMGWTFLOLSMH]

So my 2003 S430 has developed a leak I presume, and my orange light is on so the AC doesn't work. Where are the possible places it could be leaking? The lines going into the dryer and the expansion valve are 2 areas and I assume the compressor? Are there more places that are leak prone? Is it smart to replace the o-rings on the compressor when you're replacing the other o-rings on the dryer and expansion valve? Thanks for your help and thanks for the video, which was very well done.

[@masood-tv]

Thanks. Schrader valves, all connection points, lines, etc... it is best you add some dye, and then look for it. Search youtube please for the process.