mahatma

I've got this annoying problem with my climate control. It makes this loud clicking sound from under the dash whether the fan is on or off.

The only time it shuts up is when I press the button with 2 arrows (to blow air on your face & feet). It's about 2 clicks a second, and clicks 12 times before a brief pause, then it starts over......very annoying.

Any ideas here?

Also....the car never warms up when it's cold out. I suspect the thermostat is stuck open or even missing. Haven't bought a service manual yet, so can someone tell me approx where the T-stat housing is located? Thanks
It's a 1996.