Improved Answer
Actually it is located lying loose on top of the RH valve cove,r spliced into the heater hose. But this valve only controls the heater in HEAT mode and has no control over the A/C whatsoever
Behind the dash on the passenger side.
Inside the heater/ac unit close to the main unit.
on the back side of the heater control panel
The air conditioner or heater continually runs.
Behind the heater core in the HVAC assembly. The assembly is behind the radio.
Yes, the 1993 Mercury Topaz is equipped with a blower motor relay that controls the operation of the air conditioner and heater. The relay is typically located in the fuse box under the hood of the vehicle. If you are experiencing issues with your air conditioner or heater not working, the relay may be a possible culprit to check.
the answer is air conditioner
The temp blend door. It is electrically controlled by an actuator. It is located behind the dash assembly.
BIOSPHERE
If your heater is a heat pump , then yes.
heater resistor burnt out! Located under glovebox near heater motor.(held in with 2 screws) 4 to 6 wires coming from the resistor.
Heated oxygen sensor heater circuit malfunction (bank 1, sensor 1): Open or short in heated oxygen sensor heater circuit Heated oxygen sensor heater malfunction (Haynes Repair Manual)