Thermostats 36.1

What are the operating principles of different temperature-reactive components and switching components used in?

• Air conditioners

• Refrigerators

• Thermostats

• Heat pumps

How can you diagnose an HVAC system that is not operating properly?

• By checking the electrical panel

• By using its thermostat

• By inspecting the ductwork

• By replacing the filters

What is the primary function of a thermostat?

• To measure humidity levels

• To control HVACR systems

• To detect smoke in the air

• To purify the air

How does a thermostat operate in an HVACR system?

• By cleaning the air that passes through the system

• By providing electrical power to the system

• By starting, stopping, or modulating operation based on preset temperatures

• By permanently setting the temperature to a fixed value

What does a thermostat sense to perform its function?

• Light intensity

• Sound levels

• Temperature change

• Air pressure

What happens to the resistance in a thermistor when the temperature increases?

• The resistance increases.

• The resistance decreases.

• The resistance does not change.

• The resistance becomes zero.

Which component uses a high-expansion metal and a low-expansion metal to react to temperature changes?

• Thermistor

• Bimetal Helix

• Bimetal Strip

• Fluid-Filled Diaphragm

What is the purpose of coiling a bimetal strip?

• To decrease its length and reduce movement

• To increase its length and reduce movement

• To increase its length and produce more movement in response to temperature changes

• To make it look aesthetically pleasing

With which of the following does a bimetal strip work?

• Mercury switch

• Reed switch

• Sets of contacts

• All of the above

What are the two characteristics of the metals in a bimetal strip?

• They are both non-conductive and have the same expansion rates

• They are bonded and have different expansion rates

• They are both highly conductive and coiled

• They are magnetic and repel each other