WorksheetsHeating Systems Quiz
Total questions: 15
Worksheet time: 8mins
What is the first step in the sequence of operation for a gas furnace?
The gas valve opens
The blower fan starts
The thermostat calls for heat
The flame sensor activates
What is the primary function of the inducer blower in a gas furnace?
To ignite the burners
To circulate warm air through ducts
To move exhaust fumes out of the heat exchanger
To shut down the furnace if overheating occurs
How does the pressure switch contribute to the gas furnace operation?
It verifies that the inducer blower is running correctly
It ignites the gas burners
It circulates air through the heat exchanger
It prevents the furnace from overheating
What does the flame sensor in a gas furnace detect?
Carbon monoxide levels
Gas pressure levels
The presence of a flame
The temperature of the heat exchanger
When does the blower fan turn on in a gas furnace?
Immediately after the thermostat signals for heat
After the flame sensor detects a flame and the firebox heats up
At the same time as the gas valve opens
When the inducer blower stops
What happens at the end of a heat cycle in a gas furnace?
The thermostat signals shut down, and the gas valve closes
The blower stops immediately
The thermostat turns off the igniter first
The furnace shuts down without cooling
How does an electric furnace generate heat?
By burning fuel
By using heating elements powered by electricity
By using an external heat exchanger
By converting air pressure into heat
What is the function of a sequencer in an electric furnace?
It controls the gas valve
It turns on heating elements in stages
It shuts down the furnace when overheating occurs
It powers the blower motor
What is the purpose of safety switches in an electric furnace?
To speed up the heating process
To allow all heating elements to activate at once
To monitor the furnace and shut it down if necessary
To increase power efficiency
Why is a pressure switch important in a furnace system?
It prevents overheating
It verifies proper ventilation before ignition
It turns on the blower motor
It detects gas leaks
What is the function of the high-limit control in a boiler?
To turn on the gas supply
To act as a backup safety measure in case the primary control fails
To regulate water levels
To adjust the heat exchanger temperature
How does a low-water cut-off work in a boiler?
It prevents the boiler from operating if the water level is too low
It controls the heat exchanger temperature
It increases water pressure
It turns off the blower motor
What does a 24-volt transformer do in an electric furnace?
Converts high voltage to 24 volts for controls and relays
Powers the blower motor
Acts as the main power source for the furnace
Controls gas pressure levels
Why is an auto-reset transformer beneficial in troubleshooting?
It eliminates the need to replace fuses when troubleshooting short circuits
It provides unlimited voltage output
It shuts down the furnace permanently when a short circuit occurs
It increases the power supply to the furnace
What is the purpose of a limit switch in an electric furnace?
To regulate the water level in the system
To increase airflow through ducts
To shut down the system if the temperature exceeds safe limits
To replace the sequencer
