A traditional thermostat has two pieces of different metals, such as brass and I

Question

A traditional thermostat has two pieces of different metals, such as brass and Iron, bolted together to form a bimetallic strip. The strip works as a bridge in an electric circuit connected to the heating system Normally, the "bridge is down", the strip carries electricity through the circuit, and the heating is on (top part of the figure). When the strip gets hot, due to the passage of electric current, the brass strip expands more than the iron strip, so that the bimetallic strip bends Now the "bridge is up", interrupting the circuit, so that the heating is off (bottom pan of the figure). As the room cools, the strip goes gradually back to the original flat shape and the process starts again. Can you describe how would you modify this setup in such a way that it would work for cooling the room in summer? You may draw a sketch

Explanation / Answer

When a thermostat is used in an electrical circuit, its bimetallic strip gets heated and bends if the temperature in the circuit exceeds a certain limit. Hence the circuit breaks. Since there is no current in the circuit now, the temperature of the strip decreases. The strip gets restored to its original position, and the circuit is completed, allowing current to flow again.
Bimetallic strip is assembled with temperature controller system. When temperature reaches to a preset value, the bimetallic strip is so bent it closes an NO contact which initiates the cooling system to decrease the temperature of the system.

When temperature rises, due to bimetallic property, the spring twists more. Due to this mechanical deformation of the spring, a pointer attached to the dial moves and indicates the temperature, as the dial of this bimetallic strip thermometer is calibrated in temperature scale.

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