What makes the Qs AC so quiet?
What makes the Qs AC so quiet?
Just wondering because my 400e MBZ has a REALLY noisy AC. Fan really roars. Its really more of a "low level" roar but it is quite fatiguing/tiring after a short time. My 92Q is SO much more quiet - even at full blast! I was wondering if it might be generated by the fan itself and that maybe when I do the costly AC repair that is in the not to distant future that I might upgrade the fan?
I think one of the reasons is the Q uses a variable compressor which adjusts to the amount of cooling needed at any particular time.
One of my favorite aspects of the Q is the FANTASTIC HVAC system. I've never had another car that was set and forget regarding HVAC. That's probably why I'll spend HUGE money at the dealer this week to have my compressor replaced.
One of my favorite aspects of the Q is the FANTASTIC HVAC system. I've never had another car that was set and forget regarding HVAC. That's probably why I'll spend HUGE money at the dealer this week to have my compressor replaced.
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bryq45
- Posts: 27
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- Car: build computers, setup small networks, electrical work, plumbing, home improvement
Quote »my 400e MBZ has a REALLY noisy AC. Fan really roars. Its really more of a "low level" roar but it is quite fatiguing/tiring after a short time. My 92Q is SO much more quiet - even at full blast! [/quote]
I tend to agree with you Jberger. The AC system on the 95 C280 MBNZ that my mom drives is HELLA loud.
However, on the 'outside' My 93 Q45 AC system is 'louder' than hers. THe Compressor failed a month after a conversion from R12.
Quote » I'll spend HUGE money at the dealer this week to have my compressor replaced.[/quote]
IM gettin really tired of hearing that Clickity Clack sound. Plus the summer will be here soon, and Im still debating if I should get another compressor and have the system recharged. But I wouldnt be able to afford anything else. (ie. Condenser, receiver drier... and whatever else needs to be replaced when performing a full blown AC service. Plus I dunno if i wanna stay stock (R12) or convert to R134. Its still up in the air.
tkd_q45, lots of luck getting that AC fixed (i hope I can get the money from somewhere to do it too...i.e. Tax REFUND CHEK!!!)
-Bry
I tend to agree with you Jberger. The AC system on the 95 C280 MBNZ that my mom drives is HELLA loud.
However, on the 'outside' My 93 Q45 AC system is 'louder' than hers. THe Compressor failed a month after a conversion from R12.
Quote » I'll spend HUGE money at the dealer this week to have my compressor replaced.[/quote]
IM gettin really tired of hearing that Clickity Clack sound. Plus the summer will be here soon, and Im still debating if I should get another compressor and have the system recharged. But I wouldnt be able to afford anything else. (ie. Condenser, receiver drier... and whatever else needs to be replaced when performing a full blown AC service. Plus I dunno if i wanna stay stock (R12) or convert to R134. Its still up in the air.
tkd_q45, lots of luck getting that AC fixed (i hope I can get the money from somewhere to do it too...i.e. Tax REFUND CHEK!!!)
-Bry
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Q45tech
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- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Don't convert from R12 to R134a as all the components must be changed to even achieve 20% less [inferior] cooling......even the condenser is wrong for R134a!!!!!!!!
R12 is still only $40 a pound x 2.4= $100 worth but failure to replace all rubber o rings and use the correct PAG oil and flushes means leaks again.
With proper maintenance a compressor should have lasted 220,000 miles + especially in North...........owners have only themselves to blame for early failures.
"Q uses a variable compressor which adjusts to the amount of cooling needed at any particular time. " ......this is accomplished by keeping the suction pressure constant but error in charge can over work the self regulating system......AC should be vacuumed down and R12 measured [by weight] at least every 2 years [after 60k] to catch leaks early before moisture destroys the oil.
R12 is still only $40 a pound x 2.4= $100 worth but failure to replace all rubber o rings and use the correct PAG oil and flushes means leaks again.
With proper maintenance a compressor should have lasted 220,000 miles + especially in North...........owners have only themselves to blame for early failures.
"Q uses a variable compressor which adjusts to the amount of cooling needed at any particular time. " ......this is accomplished by keeping the suction pressure constant but error in charge can over work the self regulating system......AC should be vacuumed down and R12 measured [by weight] at least every 2 years [after 60k] to catch leaks early before moisture destroys the oil.
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Q45tech
- Moderator
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- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Don't talk to people who don't have a service manual [especially about detailed AC work] as Infiniti felt it necessary to include one with every Q sold.
If owners don't take the time to secure a replacement why do they deserve to be spoon fed........in school what happens if you repeatedly don't show up with your text book.
To me admitting you don't have a manual means you don't care.
R12 AC systems have been on cars since before 1950 and they have changed little in 50 years. All compressors use lube oil [it has improved in recent years]. All $7,000 AC machines have provisions to add oil at the touch of a button...........obviously flushing out the old oil is a manual operation. The EXACT amount and type of oil is critical as too little will lead to wear and too much will reduce AC efficiency drastically!!!!!!!!!!!!!!!!!!!!!!!!!!!! ...........some shops use cheap oil to save a dollar knowing problems won't show up for years.
The Federal government [EPA] requires R12 technicans to have a license but it is easy to get, hopefully they know 10 times more than the test requires.
Any AC shop will know what to do, they may tell you it's not worth it, but they are in the business of selling new compressors/evaps, dryers/condensers not doing preventative maintenance which will lower their revenue.
It is actually illegal for me to encourage or even describe thing with R12 as it might lead to an illegal discharge subjecting me to a $10,000 fine.
If owners don't take the time to secure a replacement why do they deserve to be spoon fed........in school what happens if you repeatedly don't show up with your text book.
To me admitting you don't have a manual means you don't care.
R12 AC systems have been on cars since before 1950 and they have changed little in 50 years. All compressors use lube oil [it has improved in recent years]. All $7,000 AC machines have provisions to add oil at the touch of a button...........obviously flushing out the old oil is a manual operation. The EXACT amount and type of oil is critical as too little will lead to wear and too much will reduce AC efficiency drastically!!!!!!!!!!!!!!!!!!!!!!!!!!!! ...........some shops use cheap oil to save a dollar knowing problems won't show up for years.
The Federal government [EPA] requires R12 technicans to have a license but it is easy to get, hopefully they know 10 times more than the test requires.
Any AC shop will know what to do, they may tell you it's not worth it, but they are in the business of selling new compressors/evaps, dryers/condensers not doing preventative maintenance which will lower their revenue.
It is actually illegal for me to encourage or even describe thing with R12 as it might lead to an illegal discharge subjecting me to a $10,000 fine.
Well, as luck would have it, I just heard back from the dealer on my AC problem. It was a stuck clutch which burned out the compressor (I knew that would be it).
And on the subject of converting to R134, even the dealer agrees it's a bad idea. I'm replacing the unit with R-12, new compressor and dryer and hoses. Had the Coil, Condensor and dryer replaced 20 months ago and since I just hit 200K I don't mind paying for the new compressor.
I had to talk THEM into replacing the dryer, kinda makes you wonder what kind of training they have. I thought all the early Q AC kits came with 2 dryers, one for the flush and one for the final fill.
Dennis, am I correct in wanting the dryer replaced even thought it's fairly new (20 months)? Is's still a sealed system, but I didn't think it was worth the chance to use the old one.
This is the only work I don't road trip to T3 for, it's just too far in a hot car . . .
And on the subject of converting to R134, even the dealer agrees it's a bad idea. I'm replacing the unit with R-12, new compressor and dryer and hoses. Had the Coil, Condensor and dryer replaced 20 months ago and since I just hit 200K I don't mind paying for the new compressor.
I had to talk THEM into replacing the dryer, kinda makes you wonder what kind of training they have. I thought all the early Q AC kits came with 2 dryers, one for the flush and one for the final fill.
Dennis, am I correct in wanting the dryer replaced even thought it's fairly new (20 months)? Is's still a sealed system, but I didn't think it was worth the chance to use the old one.
This is the only work I don't road trip to T3 for, it's just too far in a hot car . . .
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shaginator
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Thanks Shaggy, I went ahead and had the dryer replaced, also ended up having the expansion valve replaced also. So I've almost got a brand new system.
WOW does it blow cold. Bring on that summer heat. Also had new brakes and rotors all around. It's amazing what a new set of rotors does for the Q. Too bad they'll warp in another 2 months. . .
WOW does it blow cold. Bring on that summer heat. Also had new brakes and rotors all around. It's amazing what a new set of rotors does for the Q. Too bad they'll warp in another 2 months. . .
Q45tech - I don't have a manual for my Q45 - It's not that I don't care, it's just that I don't give a damn;)
bryq45 - glad to know that it's not just me (MBZ that is) w/loud AC. To add insult to injury, I do need a new evaporator and on a W124 it's well over $2000 to replace. You see those "genius" MBZ engineers designed the car in such a way that you have to thoroughly dismantle the interior to get to the evaporator.
I guess Germans like things to be HARSH! Along with the noisy AC, the throttle on my W124 (400e) is overly stiff (other German cars have this too) as well as the action of most of the switchgear. Guess it's their idea of "character" - I find it to be obnoxious, abrasive and at best, heavy handed.
bryq45 - glad to know that it's not just me (MBZ that is) w/loud AC. To add insult to injury, I do need a new evaporator and on a W124 it's well over $2000 to replace. You see those "genius" MBZ engineers designed the car in such a way that you have to thoroughly dismantle the interior to get to the evaporator.
I guess Germans like things to be HARSH! Along with the noisy AC, the throttle on my W124 (400e) is overly stiff (other German cars have this too) as well as the action of most of the switchgear. Guess it's their idea of "character" - I find it to be obnoxious, abrasive and at best, heavy handed.
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Q45tech
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- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
"You see those "genius" MBZ engineers designed the car in such a way that you have to thoroughly dismantle the interior to get to the evaporator. "
Many cars are this way! Kind of a trade off in positioning the heater core and evaporator.......Changing the Q heater core requires the same difficulty....say 14 hours of expert labor plus the core. And the evaporator takes only 5 hours once the system is vacuumed down!
"It's not that I don't care, it's just that I don't give a damn "
It is very repetitive and boring for those of us that do care to keep supplying answers, that are printed and available to those that have the service manual.
Many cars are this way! Kind of a trade off in positioning the heater core and evaporator.......Changing the Q heater core requires the same difficulty....say 14 hours of expert labor plus the core. And the evaporator takes only 5 hours once the system is vacuumed down!
"It's not that I don't care, it's just that I don't give a damn "
It is very repetitive and boring for those of us that do care to keep supplying answers, that are printed and available to those that have the service manual.