Hello,
The cold weather must be upon us when we have 2 heater-related posts in as many days.
Sometime over the last 6 months, the heat in my car (1966 Oldsmobile Starfire) stopped working. My Dad and I did a little poking around, and found that there was no vacuum signal getting to the heater control valve. Probably a vacuum leak somewhere under the dash. So we jury-rigged the thing by running a vacuum hose straight from the vacuum tank to the heater control valve. So now the heat works, which is nice.
However it doesn't work in the way I expected. I thought that making the H.C.V. always on would make the air always blow hot, regardless of the console temperature selector. But on my drive back home today, I found that selecting "cool" blows cold air, as well as "warm" blowing hot.
Apparently the temperature selector works independently from the heater control valve. So my questions are these:
1. What does the heater control valve do?
2. What controls it, if not the temperature selector?
3. Am I causing any harm by keeping the valve open 24/7?
Obviously, I value a warm tush, but not as much as a working automobile. So if I should be rethinking my winter driving strategy, somebody please let me know.
Mister