Quiz on Electronic Controls and Ignition Sequences

What initiates the call for heat in a forced-air furnace?

• The main burner lights

• The ignition module powers up

• The room thermostat senses a drop in temperature

• The pressure switch closes its contacts

What happens if the ignition module senses a flame during the safe-start check?

• The main burner ignites

• The system goes into lockout

• The ignition sequence continues

• The pilot gas valve opens

What is required for the ignition of the pilot in an intermittent pilot spark system?

• Only a source of ignition

• Only fuel (gas)

• Both fuel (gas) and a source of ignition

• A continuous flame sensor

What occurs after the pilot flame is proven in an intermittent pilot spark system?

• The spark generator remains on

• The main gas valve is energized

• The pilot gas valve shuts off

• The system goes into lockout

What is the purpose of the post purge cycle in some furnaces?

• To ignite the main burner

• To clear unburned gas from the combustion chamber

• To maintain pilot flame

• To shut down the entire system

What happens if the pilot is not proved within the lockout timer's allotted time?

• The system continues to try igniting

• The module shuts off the gas and spark

• The main burner ignites

• The thermostat resets

What is a recycling control in ignition systems?

• A system that locks out after one try

• A system that retries ignition multiple times

• A system that continuously runs the pilot gas

• A system that uses a standing pilot

What is the maximum warm-up time for a hot surface igniter?

• 1-2 minutes

• 17-34 seconds

• 30-45 seconds

• 10-20 seconds

What is the role of the flame sensor in the ignition sequence?

• To control the gas valve

• To sense the pilot flame through flame rectification

• To ignite the pilot flame

• To initiate the safe-start check

What happens to the main burner when the thermostat is satisfied?

• It ignites the pilot flame

• It goes into lockout

• It shuts off power to the relay

• It continues to run indefinitely