mdirollo Posted July 14, 2008 Report Share Posted July 14, 2008 Ok, this is the strangest thing that I've ever seen on any car I've owned...and I've owned MANY...According to my owner's manual, the a/c is not supposed to function when the fan control switch is set to the "O" (off) position...but it is. I've noticed that if the fan speed switch set to off and if the a/c compressor switch is depressed (the a/c indicator light is green) I get refrigerated air coming out of the vents when driving along. And this happens even from start up in the mornging. The only way NOT to get refrigerated air when the fan speed switch is already set to "Off" is to also manually turn the a/c switch off (amber indicator light) as well. This contradicts what is written in my owner's manual.Furthermore, the REALLY weird part about this whole situation is that the compressor is NOT cycling on and off (yeah, that's right...I'm getting refrigerated air without the compressor running). Here's the test I've conducted: I got in the car in the morning after it'd been sitting all night (the engine and the a/c haven't run since the previous day). The fan switch is in the "off" ("O", not "auto") positin and the compressor switch is depressed in the on position (the indicator light on the a/c switch is green). I then put an a/c thermometer in one of the center vents and then drive off. Once on the highway, the termometer is registering air temps in the vents in the low 40's (the outside temp was around 85). I then pulled over and visually inspected the clutch on the compressor for over 10 minutes with the engine running (I did not alter or change any of the above a/c or fan settings) AND THE COMPRESSOR NEVER ENGAGES! Yet, when I get back in the car and resuming driving down the highway...the air coming out of the vents is still a cool 40 degrees. Then I manually turn the a/c compressor switch off (light glows amber) and the temp readings of the air coming from out of the vents immediately starts to rise to the outside ambient temp. Again, if I hit the compressor switch, turning it back on, the air temps in the vents immediately drop back down again. So, how could this possibly be? My a/c compressor isn't cycling, yet I'm getting refrigerated air. And, according to what's writton on two separate pages in my owner's manual, the a/c function isn't supposed to work when the fan speed switch is in the "Off" setting...yet it somehow does...and withouth the compressor cycling on and off.Ok, I know this is weird and defies every mechanical concept for A/C system function...but, I swear to you, this is what's happening.If anyone else out there has similar experience or advice to offer, I'd be happy (and eager) to hear about it.Thanks in advance... Link to comment Share on other sites More sharing options...
mr. volvo Posted July 14, 2008 Report Share Posted July 14, 2008 Ok, this is the strangest thing that I've ever seen on any car I've owned...and I've owned MANY...According to my owner's manual, the a/c is not supposed to function when the fan control switch is set to the "O" (off) position...but it is. I've noticed that if the fan speed switch set to off and if the a/c compressor switch is depressed (the a/c indicator light is green) I get refrigerated air coming out of the vents when driving along. And this happens even from start up in the mornging. The only way NOT to get refrigerated air when the fan speed switch is already set to "Off" is to also manually turn the a/c switch off (amber indicator light) as well. This contradicts what is written in my owner's manual.Furthermore, the REALLY weird part about this whole situation is that the compressor is NOT cycling on and off (yeah, that's right...I'm getting refrigerated air without the compressor running). Here's the test I've conducted: I got in the car in the morning after it'd been sitting all night (the engine and the a/c haven't run since the previous day). The fan switch is in the "off" ("O", not "auto") positin and the compressor switch is depressed in the on position (the indicator light on the a/c switch is green). I then put an a/c thermometer in one of the center vents and then drive off. Once on the highway, the termometer is registering air temps in the vents in the low 40's (the outside temp was around 85). I then pulled over and visually inspected the clutch on the compressor for over 10 minutes with the engine running (I did not alter or change any of the above a/c or fan settings) AND THE COMPRESSOR NEVER ENGAGES! Yet, when I get back in the car and resuming driving down the highway...the air coming out of the vents is still a cool 40 degrees. Then I manually turn the a/c compressor switch off (light glows amber) and the temp readings of the air coming from out of the vents immediately starts to rise to the outside ambient temp. Again, if I hit the compressor switch, turning it back on, the air temps in the vents immediately drop back down again. So, how could this possibly be? My a/c compressor isn't cycling, yet I'm getting refrigerated air. And, according to what's writton on two separate pages in my owner's manual, the a/c function isn't supposed to work when the fan speed switch is in the "Off" setting...yet it somehow does...and withouth the compressor cycling on and off.Ok, I know this is weird and defies every mechanical concept for A/C system function...but, I swear to you, this is what's happening.If anyone else out there has similar experience or advice to offer, I'd be happy (and eager) to hear about it.Thanks in advance...all i can tell you is, you are not, getting any sort of cooled or refrigerated air, without the compressor running. this is not possible, there is no magic or weird science involved with this system. the compressor must pump, with the clutch engaged, for any cool air to be produced. case closed. if the compressor does not pump the refrigerant, you will not get any ac. Link to comment Share on other sites More sharing options...
Oreo931 Posted July 14, 2008 Report Share Posted July 14, 2008 This happens to me too, but I am not agreeing that cold air just appears out of nowhere...It is happening for a reason. Link to comment Share on other sites More sharing options...
mr. volvo Posted July 14, 2008 Report Share Posted July 14, 2008 This happens to me too, but I am not agreeing that cold air just appears out of nowhere...It is happening for a reason.Yes, indeed. the compressor engaging, is the reason. What is making it engage, is the question to figure out.Tim ChildersVolvo Of Hickory Link to comment Share on other sites More sharing options...
gr8gatzby Posted July 14, 2008 Report Share Posted July 14, 2008 Same here. My compressor is not engaging, yet trickle of cold air from vents. I always just assumed it was the residual cold air remaining in the system. It's always been a curious thing. Link to comment Share on other sites More sharing options...
Chilled man Posted July 14, 2008 Report Share Posted July 14, 2008 The real question are how cold is the air what is the temp outside are you sweating when this is happening what is the interior temp of the car Link to comment Share on other sites More sharing options...
mdirollo Posted July 18, 2008 Author Report Share Posted July 18, 2008 Just wondering if anyone out there can help me out with this very bizarre situation.I have a 2000 V40 - American spec vehicle, with Electronic Climate Control. According to my owner's manual, the ac compressor is supposed to be defeated when the fan/blower speed switch is set to OFF. This does not happen on my vehicle. The AC compressor switch has two indicactor lights...green for ON, and amber for OFF. If the ac compressor switch is ON and I set the fan speed switch to OFF, the ac compressor switch remains green. Furthermore, even though there is no forced air coming through the vents (the fan is defitintely off) I will still get refrigerated air through the dash vents while the car is in motion - i.e. the air is being fed into the cabin via natural ventilation. This happens even in the morning when first starting the car and the a/c has not been run since the previous day - so it's not 'residual cooling' that I'm describing here. Now, here's the REALLY BIZARRE PART: During this scenario (the fan speed switch is set to OFF and the compressor switch is ON) my compressor is NOT CYCLING on and off aAT ALL during this scenario (that's right....I'm getting cooled/refrigerated air without the compressor running). Of course, I can only check the compressor when the car is idling and I'm under the hood. Here's a little test I've conducted recently:I get into the car in the morning, put an ac thermometer in the center AC vent and take a reading after letting it sit there (the car has not been started yet). The temp reading topped out at 70 degrees farenheit. I then start the car, make sure the fan speed switch is set to off, and and the compressor switch is turned on. I get on the highway and drive. The thermometer reading drops to around 42 degrees farenheit and stays there. I then depress the ac compressor switch tp turn it off (the green indicator light on the switch turns to amber) and the thermometer reading very soon thereafter jumps back up to around 70 degrees (the ambient outside temperature). I then depress the ac switch again and, sure enough, the air temp coming out of the vents drops back down to around 42 again.So, the only way to stop getting refrigerated/cold air when the fan speed switch is off is to also set the ac compressor switch to OFF as well. No big deal...however, this completely contradicts what is written in my owner's manual which clearly states, on two separate pages no less, that the air conditioning function will not be available when the fan switch is set to OFF.Normally, I'd just shrug this off as an error in the writing of the manual. However, what's really got me puzzled is that the A/C compressor is not cycling on and off during this scenario, like it normally does when the fan speed switch is set to either AUTO or any one of the fan speeds 1 through 5. And yet, I'm getting refrigerated air without the compressor cycling on and off. And that's the part that has me wondering if there is something wrong with the ECC module and/or the AC compressor.Any advice or input on this seemingly odd situation would be appreciated.Thanks in advance to any and all who offer their input...Cheers,Mark Link to comment Share on other sites More sharing options...
dmelviØØ7 Posted July 18, 2008 Report Share Posted July 18, 2008 TOPICS MERGED Link to comment Share on other sites More sharing options...
turbomoose Posted July 18, 2008 Report Share Posted July 18, 2008 Same here in my 850Same thing in my moms '04 S40Same thing in my dad's '03 XC90 T6 ...before he killed it.Fan set to 0. AC switch left ON. = COLD air from dash vents if driving with recirculation turned off. Your AC Compressor WILL still engage and cool the outside air flowing into your car.If you want NO fan and NO AC Compressor cooled air set fan to 0 and manually turn AC button off so the little amber light next to AC OFF glows. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.