The mechanical contact thermostat can also use a simple mechanical contact instead of a mercury contact switch. As shown in the photo using a White-Rodgers mechanical thermostat, the bimetallic coil is used to move and open or close simple mechanical contact points attached to a lever arm. It also uses a heat anticipator.
Another older version of the mechanical contact thermostat uses a straight blade bimetallic strip and not a coiled strip. They are a bit less accurate but work under the same principle.
Mechanical Thermostats
Modes / Programming
The mechanical contact thermostat has modes for heating and cooling and fan positions for on/off and automatic. The thermostat is not programmable.
