Can't stop the heat

[krichard]

I cannot seem to stop heat from coming in through either the dash for defrost or the floor vent. I have gotten under the car and checked the valve as referenced in this thread and it is functioning correctly. Help! Urgent!

My ac has a hard enough time keeping up without having the extra heat added to the interior of the car. The fans are not on but when I am in motion I can put my hand down and feel the heat coming out. At idle it is hot around the vent but not blowing. I need help!!! How do I stop it?

[magilla]

Remove the ducting between the body and the flapper valve (in the rear wheel well areas).
I am in the same boat as you, except my A/C doesn't work, either.

[alibaba]

I guess it is because heat rises. Even if the heater valves are working properly, some hot air will still travel all the way up both tubes along the side, up the flexi hoses and out of the vents. It is exacerbated by the fact that the heater blower runs at low speed even when the heater is off.
Where the tube and hose meet can be found by removing the piece of interior trim where the hood cable handle is 9same on both sides). What I did was that I disconnected the flexi hoses from the tubes and placed the bottom half of a cola can over to cover the tube, so no hot air can get inside the cabin. During the winter, take the cans off and you'll get hot air back. Its only a matter of removing a few screws and you don't have to crawl under the car.

[cowtown]

There is just not much between those heat enchangers and your cockpit, krichard. The flapper boxes are the only things regulating that heat, so I'd have another look at them.

Also check to be sure your footwell blowers are operating properly (ie they turn on when you slightly lift the red heat levers, they don't run all the time). I'm sure you would hear the blowers if they were acting up, though. 99% chance that the flapper boxes are letting hot air past, even in the closed position.

[ChrisBennet]

The heater valves have a butterfly valve inside them that should seal off the air when the valves are closed. By closed, I mean that they are dumping the hot air outside.
Even without any fans going, the engine will push some air through the heat exchangers. Opening a window some will also cause a vacuum in the cabin that will suck air from the heater tubes (if the valve isn't sealing them).
-Chris

[Todd Simpson]

My drivers side flapper box cable was set 2mm too short and I got a good amount of heat coming through, even with brand new boxes. Sticky cables, sticky valves and you'll get heat. As a test, drive around with the windows closed and the heat off but directed to the defroster. Crack a window or the sunroof and feel the heat pour out of the vents.

Cheap fix. Spray the flapper box with WD40, work it back and forth, grease the cable, throw a heavier return spring on it. (Could make your car stink like WD40.)

If that doesn't work, just jam it shut or disconnect the hose from the heat exchanger. Works great until you need heat.

Replacing the flapper boxes can be done with the engine in the car, but it's a lot easier if it's out. Soak the nuts with penetrating oil, heat them up with a torch and cross your fingers you don't snap the studs. Prepare for scraped arms, busted knuckles, rust in the eye, all the usual stuff.