When is the A/C Compressor Running?
#1
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When is the A/C Compressor Running?
I'm curious as to whether the A/C compressor is running when the airflow is split between defrost and lower. On my honda, it doesn't run. But I think I may hear it kick on in my 8. I am aware that it runs in defrost mode, but there's still no light or indication beyond simply hearing it kick on. When you cycle through the different airflows, does it automatically turn on and off? I'd like to run it as little as possible to save gas, reduce load and wear, etc.
#2
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it runs anytime you have floor or a combo of floor and something else selected even if the light doesnt show it is. but it shuts off when you go over 65% of wot. so if you want to have it off when you have selected floor KEEP YOUR FOOT IN IT ![Smilie](https://www.rx8club.com/images/smilies/smile.gif)
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#3
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Yeah it probably is running if any defrost mode is picked. I would think it's running on the Honda as well because the main way the defrost works is by drying the air. In my previous car (also a Honda), I could select defrost and it would automatically light up the A/C button. I could then turn the A/C off but keep the air coming out the vents at the windshield. But if I did that, it would actually fog up worse if it was at all humid.
#5
Originally Posted by zoom44
it runs anytime you have floor or a combo of floor and something else selected even if the light doesnt show it is. ![Smilie](https://www.rx8club.com/images/smilies/smile.gif)
![Smilie](https://www.rx8club.com/images/smilies/smile.gif)
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#6
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one of the many many reports and/or articles i have read since first starting to research the car nigh on 3(or is it 4 now?) years ago. also i think its in the manual
whenever the defroster is on the ac is on and whenever floor is selected the defroster is on. no matter what the little icons are telling you. if it didnt, because of the position of the engine in relation to the ducts and the windshield, whenever you switched it to floor your windshield would fog over.
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#8
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Originally Posted by Brandon
Yeah it probably is running if any defrost mode is picked. I would think it's running on the Honda as well because the main way the defrost works is by drying the air. In my previous car (also a Honda), I could select defrost and it would automatically light up the A/C button. I could then turn the A/C off but keep the air coming out the vents at the windshield. But if I did that, it would actually fog up worse if it was at all humid.
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Originally Posted by rodmeister
That explains the cycling sensation of the engine on idle when I have the air to the floor. I suspected the A/C was cycling but couldn't believe Mazda would be so stupid. Where did you learn this?
#11
Okay, okay ... it's in the driver's manual.
This may have implications for my gas mileage since I use bi-level and low-level airflow most of the time. I'll see if I can I can improve my 16mpg.
This may have implications for my gas mileage since I use bi-level and low-level airflow most of the time. I'll see if I can I can improve my 16mpg.
Last edited by rodmeister; 12-10-2004 at 06:18 PM.
#13
Originally Posted by zoom44
whenever floor is selected the defroster is on. no matter what the little icons are telling you.
#14
Rather than rely on the manual, which might be incorrect, I investigated the A/C compressor runtimes directly by ear and tach. - First I familiarized myself to the sound of the A/C compressor while idling at stop signs. I could hear a solenoid or something "clunk" whenever I selected A/C. At the same time the tach would blip slightly momentarily. I also could hear the engine take on a deeper tone when the compressor cycled every couple minutes with all the previous sounds and tach indication. - Then I selected the air-circulation modes. With The A/C off, I did not detect a "clunk" or cycling on the dash-only mode or regular dash/floor mode. All other air modes, including floor-only mode made the characteristic sounds of cycling. - I'm disapointed with the floor-only mode cycling the compressor, since I use it a lot, because I dislike having hot air blown at my face and chest. On cool nights I like to drive with open windows and hot air blowing at my feet. Since I use the floor-only mode almost 50% of the time, it must be hurting my gas mileage. I'll avoid the compressor modes and check my mileage
Last edited by rodmeister; 12-15-2004 at 09:17 PM.
#15
Metatron
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Mileage.....
If you want to check the 'non-a/c' mileage without giving up your hot feet, you can pull the fuse to the a/c clutch.
The clutch has its own fuse, 10 amp, bottom of the engine compartment fuse box. Then you know for sure, and can generate some real comparison figures, yet still enjoy (most of) the modes you want.
S
The clutch has its own fuse, 10 amp, bottom of the engine compartment fuse box. Then you know for sure, and can generate some real comparison figures, yet still enjoy (most of) the modes you want.
S
#16
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![Angry](https://www.rx8club.com/images/icons/icon8.gif)
(Rant On)
It’s been cold here late…well by California standards…30s in the morning. It is seriously Pi$$ing me off having the A/C turn on when I’m trying to warm up the interior of a cold car. If I put the heater on High and on the Floor vents—Hey, my feet get cold J I expect un Air Conditioned air. I mean, the car is warming up and I’m trying to get some HEAT going.
This is absurd! This is a gas waster and feet cooler.
Also, having the AC run all the time creates condensation in the AC evaporator (it’s like a little radiator under the dash that cools instead of heats). That leads to the musty dash vent smell. Yes, I can blow things out with the dash vents before I shut off the car, but this is just stupid after running the car with the floor heater on.
Are there some Electrical Engineers that could help with where to cut and wire in a switch? Can some Common Sense be "Flashed" into whatever computer controls the AC?
Also, I think I’m going to embark on a Mazda Technical Crusade. People who buy sports cars like to have control of their "driving experience"
Here's to Death or victory…
BTW, I think this is a result of Fords influence on Mazda. Ever tried to control the AC on a Ford…
It’s been cold here late…well by California standards…30s in the morning. It is seriously Pi$$ing me off having the A/C turn on when I’m trying to warm up the interior of a cold car. If I put the heater on High and on the Floor vents—Hey, my feet get cold J I expect un Air Conditioned air. I mean, the car is warming up and I’m trying to get some HEAT going.
This is absurd! This is a gas waster and feet cooler.
![Mad](https://www.rx8club.com/images/smilies/mad.gif)
Also, having the AC run all the time creates condensation in the AC evaporator (it’s like a little radiator under the dash that cools instead of heats). That leads to the musty dash vent smell. Yes, I can blow things out with the dash vents before I shut off the car, but this is just stupid after running the car with the floor heater on.
Are there some Electrical Engineers that could help with where to cut and wire in a switch? Can some Common Sense be "Flashed" into whatever computer controls the AC?
Also, I think I’m going to embark on a Mazda Technical Crusade. People who buy sports cars like to have control of their "driving experience"
![Roll Eyes (Sarcastic)](https://www.rx8club.com/images/smilies/rolleyes.gif)
BTW, I think this is a result of Fords influence on Mazda. Ever tried to control the AC on a Ford…
Last edited by RotaMotion; 12-29-2004 at 03:42 AM.
#17
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Originally Posted by RotaMotion
BTW, I think this is a result of Fords influence on Mazda. Ever tried to control the AC on a Ford…
#19
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Originally Posted by dmp
Looks like no more feet&dash venting for me.
:-/
![Frown](https://www.rx8club.com/images/smilies/frown.gif)
Please correct me if I'm wrong, anyone.
#20
RX8 and a Truk....
Originally Posted by khtm
From what I've read...it's not JUST feet&dash venting, it's also dash venting alone...?
Please correct me if I'm wrong, anyone.
Please correct me if I'm wrong, anyone.
Right... both of those options are off limits now.
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#21
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Originally Posted by dmp
Very crappy information - I'm annoyed as well at the 'AC on all the time' policy for this car. ![Frown](https://www.rx8club.com/images/smilies/frown.gif)
Looks like no more feet&dash venting for me.
:-/
![Frown](https://www.rx8club.com/images/smilies/frown.gif)
Looks like no more feet&dash venting for me.
![Frown](https://www.rx8club.com/images/smilies/frown.gif)
The "A/C down your throat, like it or not" happens if you select "defroster and floor vents", "defroster vents", or "floor vents".
For "dashboard vents" or "dashboard and floor vents", A/C should only be on if you pushed the A/C button to on.
#22
RX8 and a Truk....
Originally Posted by rx8cited
"Feet&dash venting" as you say or "dashboard and floor vents" should not cause the compressor to come on unless the A/C button is depressed to turn the A/C light on.
The "A/C down your throat, like it or not" happens if you select "defroster and floor vents", "defroster vents", or "floor vents".
For "dashboard vents" or "dashboard and floor vents", A/C should only be on if you pushed the A/C button to on.
The "A/C down your throat, like it or not" happens if you select "defroster and floor vents", "defroster vents", or "floor vents".
For "dashboard vents" or "dashboard and floor vents", A/C should only be on if you pushed the A/C button to on.
er?
Dash + Floor = No A/C unless AC button is depressed
Dash = A/C on
Floor = A/C on
?
that right?
#24
RX8 and a Truk....
Originally Posted by Nubo
As far as I know, "dash vents only" is the ONLY non-AC setting. I guess I could just check the car.... ![Roll Eyes (Sarcastic)](https://www.rx8club.com/images/smilies/rolleyes.gif)
![Roll Eyes (Sarcastic)](https://www.rx8club.com/images/smilies/rolleyes.gif)
I get no change in Idle or sound when I switch thru the settings...including when I hit the A/C button.