Last post on Sep 30, 2013 at 7:06 PM
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Heating / Cooling
#797 of 839 Re: 2001 Tahoe heater that blows lukewarm air [wolferman1]
Jan 11, 2010 (4:32 pm)
The coolant has been changed at least once a year for the last five years. The blend door is working like it should. The coolant hoses are hot going in and coming out.The blower is also blowing a lot of air. Help again..
If you have heat at BOTH coolant hoses of 150+ degrees, then the blend door is NOT working properly.
If the blend door is not shutting all the way, it allows cool air from the A/C core in the heater. Which cools the air down.
How did they determine that the blend door was shutting completely?
#798 of 839 Inspecting AC system on vehicle before summer months
Jan 29, 2010 (6:47 pm)
I owned my Honda Accord for over 12 years. 3 of these years, I was caught off guard when my AC
system was less than adequate when the summer months hit. The best example was when I was driving to Las Vegas
in 116 degree weather and discovered the hard way that my AC was'nt up to the job. One year it was a problem with the
evaporator, the two other years it just needed a refrigerant refill.
I would like to prevent these suddent discoveries in the future. Before the summer months hit, I will ask my mechanic
to inspect the AC system. Should this be done every year? Can this be done when the weather is still cooler? What
specifically should I have my mechanic check. How many hours of labor should this cost me?
#799 of 839 Re: 2001 Tahoe heater that blows lukewarm air [0patience]
Jan 29, 2010 (7:00 pm)
Are both heater hoses so hot after the car's been running for 20 minutes and more that they are too hot to hold with bare hand for more than a few seconds?
Also with the blower on a high speed, and the heater set for HOT, the hoses should be nearly the same temperature. If one is cooler, that means the flow of coolant is not fast enough to keep it from losing too much heat to the air flow to really heat the air to maximum.
Low flow could be partly clogged heater core. Did it have DexCool when new? (Yes) Was other green antifreeze, old style green added? If so the coolant turns to globs and looks thickened in the reservoir. Professional flush.
Water pump may not be moving coolant properly? Open the radiator with the engine cooled a few minutes to relieve pressure on the system.Then start the motor and see if you can get the coolant to flow noticeably from the high pressure hose when someone accelerates the motor. Or you can accelerate it with the engine end of accelerator cable at the throttle body. It may take a few minutes for the thermostat to open again as the engine warms.
Most likely your blend door isn't closing all the way, if the first two are okay. My understanding is that all incoming air goes through the AC evaporator. Then a door forces none, part or all of the air to go through the heater core. If the blend door doesn't quite close all the way, some 30 deg outside air mixed with the air that does get forced through the heater core really cools down that air at the vents.
#800 of 839 Re: 2001 Tahoe heater that blows lukewarm air [imidazol97]
Jan 29, 2010 (11:30 pm)
'01 Tahoe came with dexcool.
#801 of 839 Re: 2001 Tahoe heater that blows lukewarm air [obyone]
Jan 30, 2010 (5:24 am)
>came with dexcool.
Yes, it did. I was hinting around to suggest someone had put in standard green antifreeze and caused the DexCool to glob up. Another factor is the DexCool may not have been changed at 3 years or earlier, like some suggest. In a few cases, just like with any antifreeze left in too long, strange things begin to happen as chemical components wear out.
A few people have had heater cores blocked partly with the globs of crud.
#802 of 839 Temp Drop Through Air Conditioner ?
Jun 02, 2010 (6:40 pm)
How much should the air temperature drop from ambient after going through a car air conditioner ?
#803 of 839 Re: Temp Drop Through Air Conditioner ? [alternator]
Jun 03, 2010 (4:01 am)
The drop depends on the ambient temperature, the humity of the air, and the heat of the sun. The factory service manual gives a chart of the expect temps at the CENTER dash outlet.If you have a thermometer from an auto store meant for AC, stick it int he center outlet and drive. Unless the sun is very strong and the humidity is very high, I'd expect it to show about 60 after many minutes of steady driving with the fan on medium speed. I have not checked the manual.
#804 of 839 Re: Temp Drop Through Air Conditioner ? [imidazol97]
Jun 03, 2010 (5:44 am)
I wonder if a 25 degree F drop in an average day ambient of 88 degrees F is about normal ?
Jul 22, 2010 (1:22 pm)
my a/c doesnt work or doesnt trow the air cold when am stop or on parking it a 2003 montana pontiac
#806 of 839 Re: a/c [pashuko]
Jul 23, 2010 (7:52 am)
Could be a nunber of things, one quick thing to check is the condition of the cabin air filter(s) if so equipped.