The Lover

Hello Members

Sorry to post this A/C problem , but I searched the forum and couldn't find a similar issue like mine

I changed the A/C Comp last year + Condenser , and it worked perfect

couple of weeks ago , my A/C start to act weird , if I started the car early morning when the weather is cool , the A/C work well , if I didn't start the car til 1-3 pm , noon time , and the weather is hot , like now summer , the car will only blow hot air , some times not most times I push the gas pedal a few times and the cool air comes , but now it only blow cold air like normal A/C when the sun is down or early morning , if it's noon , I will be cooking inside !!!

another issue is when the A/C is working well I hear a low whispering coming from the A/C inside the car , like there's a small canary singing


If any ask for the codes / fault test codes , please tell me the way to get them


sorry for my bad English

Thank you

The Lover

come on guys I need some help please
burning here from hot sun

snowmuch

Same problem here

The Lover

Then we need some experts to answer hehehe
what's the stupid a/c benz install in their vehicles !!!

The Lover

come on guys I really need help here

Carsy

I would check the gas pressure first. You may have a leak.

The Lover

the ref pressure is still the same since 3 months

JimPap

I had an A/C problem last year that presented itself as higher than normal radiator fan speed. It was receiving a signal that the a/c was getting hot and ran faster trying to cool it down. Turned out to need a condenser replacement, drying replacement, cleaning out the system and about $1,500 of my money.

I had other work done on the a/c prior to this and I can't help but believe that a dryer bag the dealer installed ruptured and caused the later problem.

Might not be related to your problem but thought it might help

Best of luck.

Acapulco Bill

@The Lover, OP: since you asked, IMO it's the clutch pulley that is sticking, as when you rev the engine the agitation causes the clutch to engage, then it wont disengage. Simple to take care of if it is just a cleaning and lubrication problem, more difficult if the magnetic clutch mechanism is worn or defective, meaning replacement.

Since it sounds like you have an older W204, recommend you see an independent Merc/Euro car shop that also services air conditioning as a specialty, to get a quick diagnostic and more economical repair if necessary, if it isnt a simple issue of cleaning and lubricating the pulley's clutch mechanism.

Carsy

I understood that the A/C had no clutch just variable vanes. JC

http://www.automotive-air-conditioni...rt=Compressors

The Lover

@Acapulco Bill you mean if the magnetic clutch mechanism is worn or defective, meaning replacing the A/C Compressor !!!
and how should I clean it and solve the lubrication problem please ?
also another hint , if the weather is hot , the cold air won't come at all , and also at night it works by it self , but when the A/C works at night , first 2 minutes left vents blow cold and right vents blow warm , later all cold together
so now the rev engine won't work any more if the weather is hot and I haven't started my car since early morning
please help solving the issue because in my city there's only 1 MB service center and they told me they can not accept my car until they give me an appointment which is three weeks later

Carsy

https://mbworld.org/forums/c-class-w...rn-off-ac.html

Acapulco Bill

Post #9 states clearly the recommendation to find an indy shop that specializes in both German car and A/C repair. May be something simple and inexpensive to fix.

Another recommendation is to find a MB dealer that provides SERVICE not excuses.

The Lover

to update my thread

when the weather is hot , and i didn't use the A/C at morning just use it at noon when it is over 33C , the A/C doesn't blow cold air , even if i do rev , but early morning , night or even noon when weather's under 33C , the A/C works perfectly but first the right vents blow kinda warmer air than the left vents , 1 minutes later all blows the same cold air
so what you think guys
especially Acapulco Bill
and my ref pressure is around 13
Help is appreciated very much

Drazil

I had an AC problem on my old W211 where the AC would only blow cold air during the early morning, but in the afternoon it was scorching hot. It turned out to be a module in the engine bay directly behind/below the middle of the windshield. That module controlled the changeover between AC and heat, and it was failing whenever it got too hot, so sometimes it would get stuck on the heat side. It was like $2xx to replace if I recall correctly. Not sure if our w204's system is similar but I throw it out there as a possible cause...

The Lover

Drazil to be sure at least provide the part number so i check if the w204 has it

Thanks

arketect

Well, im bringing up this old thread because I have the same problem. If the vehicle sits for a few hrs and the outside temp is like 90, the car blows heat for a few mins and then suddenly kicks over to cold a/c. No answer has been posted, so if there is one, great. I have an appt at the dealer on Thursday to see what the cause is. If anyone is interested, ill post the results.

sege

Same problem here annoying when it has been a 40+ C day and it takes five minutes to blow cold air. My jeep does it immediately and they were cousins! My dealer says its just the way it is designed.

Mr.Mango

Stupid question OP, but did you put new oil in the compressor when you changed it?

Merserybenze

was this fixed? I have the same problem and now it starts warm for 5-15 mins before it will blow cold when the weather is 80 plus and the car has been sitting...

que4dog

I have the same problem on a 2011 Mercedes Benz. Did anyone find the solution?

HBguy

I have worked on evety type of hvac equipment imaginable, including chillers, boilers, cooling towers for skyscrapers and down to window units and cars. I mention this because i mean no offense but:
1. Automotive ac work is never under any circumstances a DIY project. Forget diagnosing it and stick with cabin filters if you want to use tools.
2. Most wrench turners for pay are mechanics, not technicians. This is also true among those who work on auto ac.
3. Its a mercedes, therefore it is not simple.

The fact that you had work done will keep anyone with technical experience from guessing on what could be wrong because at this point, anything goes. You had a condenser and a compressor replaced? Neither go bad from driving alone.

Take it to a specialist who will guarantee his work.

rick dees

enjoy mostly all discussions re autos, mechanical, etc., Accessed tonite, as a neighbor could not stop horn on his MB. I was amazed that a MB would have such an issue. Yet I see other MB owners have had same issue. Re AC, sigh, I still drive a 74 Chevy Monte Carlo, have kept it up very well, long ago, upgraded AC from R12 to R134, have always done my own AC work. Of course, use a good mechanic/shop for the needed system vac, pressure check, and recharge. A year or so ago, replaced the compressor, did the work myself, then mechanic did the rest, said my installation of the compressor was fine. I agree that AC is not DIY, as it requires proper gauges, vacuum, tools and knowledge. My knowledge of the mechanical stuff is good, but, still want my mechanic to do the final work, as to by the numbers, recharge. Here is Las Vegas, hot whew in summer, and AC quite cold. I did upgrade to a 4 core radiator, they called it a Desert Cooler, and the fan clutch, 180 degree has been replaced a while back. People always ask me how I can keep a 45 year old car running so good. Always do all proper and proactive upkeep. And find a good mechanic who you absolutely trust.

SmellyRoses

A new year bump for a resolution

im having the same issue, air con doesn’t kick on in hot temps of the day but will work early korning

did anyone have a fix for this? I’ve re gassed and checked for leaks. All passed

when air con does work, it works great

NZ-Merc

To answer this thread I has same problem when the car was left in the hot sun the a/c would not kick in or if it did it was a random thing.

The problem is the system has slightly too much refrigerant (over charged) in the system, if a small amount is removed the a/c will work like normal.
If you do not have the tools take it to a shop ask them to remove some gas, lower the level so you can try it for a few days.
This was the cause of mine and after removing some gas the system has performed perfectly since over the last 2 years.



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