Honeywell Trol-A-Temp MCSR Mastertrol Changeover Switch Replacement
The MastertrolT Changeover Switch Replacement, Model MCSR, is a rotary selector
switch used to be a central changeover control between the HEAT-OFF-FAN-COOL Modes and control the operation of the Fan, either constant (ON) or automatic (AUTO).
The MCSR fits into any single gang, 2x4 junction box and requires a maximum of 8 wires. This is a direct replacement of the Trol-A-Temp MCS-2, MCS-3, MCS-5 and MCS-8 changeover switches. The MCSR is a much more finished appearance with an attractive polished brass faceplate. Wiring is also easier as its terminal connections are push-in wiring blocks in place of screw terminals.
The MCSR is manually switched between the modes and changes over all zones
simultaneously between the HEAT-OFF-FAN and COOL modes.
HEAT Mode - All thermostats make on temperature fall to make a call for heating.
OFF Mode - There is no power to any thermostat therefore no zones can call for heating or cooling. The Fan can be turned on by placing the Fan switch to ON.
FAN Mode - All thermostat make on temperature rise and activate the Fan ONLY.
COOL Mode - All thermostat make on temperature rise to make a call for cooling.
FAN ON - Turns the fan on continuously.
FAN AUTO - The Fan will come on only with a call in the Fan and Cool modes. In Heating the fan is typically brought on by the furnace fan control. By placing the FIH jumper on the back of the switch across both pins will provide for the fan to come on with a call for heating.