replaced heater valve, still constant heat
06-22-2010, 06:10 PM
#16
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Check the output temp within one minute of cranking the engine.
Check the output temp after the engine is warm with the hood up.
Check the output temp after the engine is warm with the hood closed.
The temps will tell you whether your problem is with coolant flow thru the heater valve or hot air coming into the HVAC inlet, which is the hole at the base of the windshield. Also check the oval rubber flap about a foot down the firewall on the passenger side. It needs the leaves and crap cleaned out occasionally, and the flap should be nearly air-tight.
Check the output temp after the engine is warm with the hood up.
Check the output temp after the engine is warm with the hood closed.
The temps will tell you whether your problem is with coolant flow thru the heater valve or hot air coming into the HVAC inlet, which is the hole at the base of the windshield. Also check the oval rubber flap about a foot down the firewall on the passenger side. It needs the leaves and crap cleaned out occasionally, and the flap should be nearly air-tight.
Check the output temp within one minute of cranking the engine = 82 deg
Check the output temp after the engine is warm with the hood up = 118 deg
Check the output temp after the engine is warm with the hood closed = 115 deg
Then I did one more...check the output with the engine warm, the hood closed and the temp slider in the car all the way to HOT = 170 deg.
Oddly enough, the temp increased with the hood up. I figured it would be the other way around. And I tested it a few times...same result. Odd. My instrument was a digital meat thermometer.
So what do the results tell me. I'm not sure. But obviously the new hot water valve is doing something because it's making the temp rise 55 deg from 115 to 170. I bought the rear hood seal and will install that when it comes... but i have a hard time believing that that alone will help keep the air temp cooler, like in the 80s. But I guess we'll see.
06-22-2010, 09:41 PM
#17
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Prior to installing it, I tested the metal one just for the hell of it, and water dribbles through it as well. Not as quickly as the original valve, but still goes through. After install, I'm still getting warmer air up front. Although the center vent appears to be an AC/warm air mix, I'm noticing warm - almost hot air coming from the d.s. footwell area.
06-22-2010, 10:08 PM
#18
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Are you sure the heater valve is closing? Even if the vacuum system is working perfectly, the valve may not close when you switch the climate control ON if the mixing motor is seized/broken. The mixing motor is on the left side of the heater core box inside the car. You need to remove the left side package tray and console side cover to see it. If it is broken, the heater valve will only close if you put the control slider to the OFF (far left) position. You should see the lever arm on the mixing motor move as you move the temp slider. If not, that's your problem.
