A/C Maintenance Question

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Is there some type of preventive maintenance I should do on my cars A/C system, or do you just wait until something goes bad and then address it?
 
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 Originally Posted By: ThirdeYe
Run it at least once a week, even in the winter. At least that's what it says in my owner's manual.
I 2nd that... many years ago the mechanics advised my dad to do the same.
 
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Virtually nobody does it but it is recommended to pump the system down and replace the dryer bag every 4 years or so. I intend to do this because I plan on driving my car a long time (and I spent $1100 on a new compressor not long ago).
 

Kestas

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That seems like a silly recommendation. The dryer bag is there to scavange any moisture in the system. Opening the system up to replace the bag would likely introduce the same amount of moisture again. Not only are you back to square one, but now you have the added expense of labor, freon, and other materials to swap it out. Also, there is a great likelihood of screwing something up on a perfectly good working system.
 
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 Originally Posted By: Kestas
Not only are you back to square one, but now you have the added expense of labor, freon, and other materials to swap it out.
R12 hasnt been used since the early/mid 90's. the "name" for r134a is DuPont Suva.
 
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 Originally Posted By: Paul56
 Originally Posted By: ThirdeYe
Run it at least once a week, even in the winter. At least that's what it says in my owner's manual.
I 2nd that... many years ago the mechanics advised my dad to do the same.
Most cars have the AC compressor running when you put the selector on "defrost". It dehumidifies the air so your windows don't fog up.
 
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Yeah, Im with Kestas. Opening up a sealed system to replace the dryer does not make much sense. What DOES make sense is replacing the dryer when you open up the system for any reason. Was it replaced when the compressor was done?
 
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 Originally Posted By: ThirdeYe
Run it at least once a week, even in the winter. At least that's what it says in my owner's manual.
What that's supposed to accomplish is to redistribute the compressor oils that may have pooled in the system. I suppose a week is enough that there still might be a good layer of oil. I'd note that most modern front defrost settings turn on the A/C by default (if there is one). The A/C is supposed to dry the air. I can clearly hear the compressor engaging when I switch to the front defrost settings.
 
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 Originally Posted By: Kestas
That seems like a silly recommendation. The dryer bag is there to scavange any moisture in the system. Opening the system up to replace the bag would likely introduce the same amount of moisture again. Not only are you back to square one, but now you have the added expense of labor, freon, and other materials to swap it out. Also, there is a great likelihood of screwing something up on a perfectly good working system.
Agree. Beside, opening up a system isn't that big of a deal just having a certified guy to vacuum and charge up your freon is $100 to me. Wait till something break before you open it up and replace the dryer like Onmo'Eegusee said.
 

TurboLuver

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So it wouldn't be advantageous to have a 7 year old system evacuated, flushed and recharged?
 
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Don't dump the system to 'drain' water or get a new receiver dryer. Since the system is pressurized, no additional water will get in there. Ford says car AC systems lose about 7 ounces average each year. By seals and right through the rubber lines [small molecules]. Using your defroster in winter usually turns on the AC. This is because they want you to use it and keep the oil circulated, instead of poling or separating. It's good for seals and leakage. If you are holding pressure, there is not much you can do. Like mentioned, keeping the condenser clean helps.
 

Kestas

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Most of the benefit from exercising the system is to keep the shaft seal wet at the compressor. Keeping the seal wet helps keep the refrigerant from leaking out.
 
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I'm sure Kestas is fully aware along with half of the free world that R-12 is no longer used in modern cars and ceased to be produced in the 90's. Freon is merely an expression. Its like calling a internal combustion engine a motor. Maybe I didnt catch it but did the OP mention the year of his car. Maybe its old and has R-12. In that case it starts to get real expensive.
 
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 Originally Posted By: TurboLuver
So it wouldn't be advantageous to have a 7 year old system evacuated, flushed and recharged?
If the system is cooling off the car and the compressor is not short cycling, I would leave it alone. If you suspect you need a charge because refigerant was lost due to normal circumstances you can have the system topped off. 7 years is a long time and some gas might have seeped out, I would have it topped off. I would only evacuate the system in the event of a leak, or the need for a repair. JMO
 
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 Originally Posted By: TurboLuver
So it wouldn't be advantageous to have a 7 year old system evacuated, flushed and recharged?
Not really.
 

TurboLuver

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Actually the system is in perfect working order, it gets very cold. I just want it to stay like it is.
 
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 Originally Posted By: PandaBear
 Originally Posted By: TurboLuver
So it wouldn't be advantageous to have a 7 year old system evacuated, flushed and recharged?
Not really.
Don't fix anything if it not broken. I notice it is always the people who drive with their windows down the bulk of the time always have problems with the A/C. The ones who always keep their windows up and use the A/C all the time usually never complain.
 

Kestas

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My significant other was one of those who drove with the window down in hot weather. When I asked her about it, she told me she was "saving" the a/c and trying not to wear it out. I set her straight and explained the folly of such thinking. Wearing out the a/c may be true in the southern climes, but not in Michigan. Here they usually fail from corrosion (hose joints and clutches).
 
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