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For some reason I just have not been able to master this climate system. Whenever I turn on the air the windows start fogging up. Usually it’s worse than this but I just wanted to send a pick so people would know what I mean.
If it's on the outside, then it's normal and climate related: exterior moisture content (high humidity) + temperature variance (significantly colder inside than outside) = condensation. The temperature of the air coming out of the vents may be too cold - nothing to worry about unless it really bugs you.
If you feel inclined to adjust the temperature of the air coming out of the vents (not the dials, the dials set the desired temperature to stop blowing the cold air, not the temperature of the air itself), it can be easily adjusted with an r134 kit (available at your local Walmart). Read the instructions, check the pressure, and adjust as indicated in the pamphlet.
If it's on the inside though.. you may have a moisture problem. Likely not too concerning. However.....
Does the vehicle smell a little funky? Does the windshield fog up a bit when the vehicle sits in the hot sun for a day? If so, water may be collecting inside the vehicle somehow. Check for signs of moisture *under* the driver and passenger footwell carpets (the foamy part), or in the battery compartment under the passenger seat.
On a humid day, with the a/c running, you should see water collecting on the pavement beneath the vehicle, just behind the front wheels (about 18 inches in) on either side. If you don't, then the a/c drain hoses may be clogged and water might be pooling in the footwells - this would be your moisture source - search this forum for threads on the topic. ie. 'water intrusion'.
this is normal at the beginning of the cooling cycle. if it persists 5-10 minutes after that it is either water in the evap coil enclosure (bad drains as mentioned above) or you are low on refrigerant and conditioned air coming out of the vents is too cold causing the condensation on the window on the inside.
If it's on the outside, then it's normal and climate related: exterior moisture content (high humidity) + temperature variance (significantly colder inside than outside) = condensation. The temperature of the air coming out of the vents may be too cold - nothing to worry about unless it really bugs you.
If you feel inclined to adjust the temperature of the air coming out of the vents (not the dials, the dials set the desired temperature to stop blowing the cold air, not the temperature of the air itself), it can be easily adjusted with an r134 kit (available at your local Walmart). Read the instructions, check the pressure, and adjust as indicated in the pamphlet.
If it's on the inside though.. you may have a moisture problem. Likely not too concerning. However.....
Does the vehicle smell a little funky? Does the windshield fog up a bit when the vehicle sits in the hot sun for a day? If so, water may be collecting inside the vehicle somehow. Check for signs of moisture *under* the driver and passenger footwell carpets (the foamy part), or in the battery compartment under the passenger seat.
On a humid day, with the a/c running, you should see water collecting on the pavement beneath the vehicle, just behind the front wheels (about 18 inches in) on either side. If you don't, then the a/c drain hoses may be clogged and water might be pooling in the footwells - this would be your moisture source - search this forum for threads on the topic. ie. 'water intrusion'.
it sounds like the air coming out is too cold cause if I turn the air off then it goes away. But then its hot as hell in the vehicle. I don't want the air on me feet and I thought if I put it high (up position) then it will hit the window more so I do my best to keep it blowing out in the middle but for some reason the window still fogs up. I will look more into this r134 because its more of a safety thing cause it hard to see vs a just bugs me thing.
this is normal at the beginning of the cooling cycle. if it persists 5-10 minutes after that it is either water in the evap coil enclosure (bad drains as mentioned above) or you are low on refrigerant and conditioned air coming out of the vents is too cold causing the condensation on the window on the inside.
its interesting that you say that because in my 2001 S500 anything below 70 on the climate dial is super icy but on my GL450 I have the dials ALL THE WAY to like 62 and it gets cool but if I put it up to 70 like I do in the S500 then it doesn't get very cool. maybe I need to check the freeon?
r134 = refrigerant = freon. If you decide to purchase the kit, be sure to get the one with the pressure gauge - priced around US$25.00 to US$30.00. Otherwise you won't know how much refrigerant to add.
The temperature variance you notice is due to the mixing of conditioned air (from the a/c evaporator) + exterior air. Turning the dial to a higher temperature setting causes warmer air to be mixed-in, which results in the cabin temperature rising. It does not change the temperature of the air coming from the a/c itself, just the mixture coming from the vents (I hope this makes sense).
Also, there may be some significant design differences in the a/c systems for the SL vs GL that account for your observations. Square footage and engine size come to mind. The GL is a much larger vehicle and there is more interior air to be moved/cooled. This works in the same way as your home a/c system: an under-powered unit will not cool/heat your home comfortably, whereas an over-powered unit will make it seem to cold/hot. The desired temperature is controlled by the thermostat/dials.
r134 = refrigerant = freon. If you decide to purchase the kit, be sure to get the one with the pressure gauge - priced around US$25.00 to US$30.00. Otherwise you won't know how much refrigerant to add.
The temperature variance you notice is due to the mixing of conditioned air (from the a/c evaporator) + exterior air. Turning the dial to a higher temperature setting causes warmer air to be mixed-in, which results in the cabin temperature rising. It does not change the temperature of the air coming from the a/c itself, just the mixture coming from the vents (I hope this makes sense).
Also, there may be some significant design differences in the a/c systems for the SL vs GL that account for your observations. Square footage and engine size come to mind. The GL is a much larger vehicle and there is more interior air to be moved/cooled. This works in the same way as your home a/c system: an under-powered unit will not cool/heat your home comfortably, whereas an over-powered unit will make it seem to cold/hot. The desired temperature is controlled by the thermostat/dials.
That makes a lot of sense and I appreciate your insight...I’ll check the Freon first!
Yeah, that air at 62* should be COLD. Definitely get that vac'd out and recharged. And maybe have the garage add a dye to check for leaks.
Also, make sure your setting is on "recirculation". If it's set to bring in outside air, then you're constantly bringing in moist air as opposed to letting the AC dry the air.
The windshield is fogging externally for the reason given above, and because the windshield ducts are selected on the control panel. On all vehicles I have owned, I do not use windshield ducts when there is a desire for cooling in the vehicle. I use the face vents only. Try selecting face vents only, and take a photo of the windshield as in the photo above.
this is normal at the beginning of the cooling cycle. if it persists 5-10 minutes after that it is either water in the evap coil enclosure (bad drains as mentioned above) or you are low on refrigerant and conditioned air coming out of the vents is too cold causing the condensation on the window on the inside.
Yup. I have this in one of mine and I hear a sloshing sound whenever I take turns too hard after a period of rain....slow drain in evap coil enclosure.
As long as it doesn't smell of sweet antifreeze inside your heater core should be fine, i.e not leaking.
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