does this sound like it's a problem with the heater control valve?

when climate control is set to 'auto' or any sort of cooler temperature, sometimes (at random) it sounds like the dampers readjust automatically and i start getting hot air blowing, even though the AC is on and i can clearly hear the AC compressor working.

most of the time, climate control works fine, so i know that the AC actually works. it's just, sometimes i start getting hot air all of a sudden. and then if i leave it or fiddle with the temperature settings a little, it'll fix itself and i get cool air again.

thanks

 

it could be.
Have you physically looked at the valve to make sure the lever isn't binding or if the arm is gunked up?

 

haven't had a chance yet, and i'm looking for documentation on how to access the valve...any leads?

 

It is not the heater control valve, that is not what it does. The heater control valve only moves when the air mix control motor moves. The mix motor and the valve are connected via a cable that run through the firewall. Even if the heater control valve is stuck in the on position the a/c will still blow cold. The heater control valve shuts the flow of coolant to the heater core off when the climate control is set to the colder settings. It helps to keep the cabin from having excess heat when the a/c is on. However it does not effect the temperature of the air coming out of the vents. Many vehicles don't even have heater control valves, they just let hot coolant flow through the heater core at all times.

 

ok, so when the air from vents starts getting hot for a while even though the AC is on, could it not be that the control valve opens when it's not supposed to?

update: it's gotten cooler, and i notice the air blows cold even with the temp setting higher to about 25C. only when i turn the air up to maybe 28C or HI does the air start to heat up...

 

I have the same issue. Any resolution on this?