Heater Problem Solved!

Like several other postings, my heater was blowing cold only. I found that the interior of the heater vacuum switch (connected to radiator lines in the engine compartment and operated by vacuum) had disintegrated and hot water was not being directed to the heater radiator. I bypassed the switch and heater blows hot.

Is this the switch located on the coolant hose going into the heater core?

If so, was the vacum line still moving the switch (tab, whatever it's called) in and out?

I've had the same cold air problem, but never thought about replacing that switch because it appeared to still be working properly (at least from the outside).

Thanks!
Dave