HVAC 105 GAS HEAT CERTIFICATION
TEST EXAM 2026 STUDY QUESTIONS
WITH CORRECT SOLUTIONS
GUARANTEED PASS | RATED A+
, HVAC 105 GAS HEAT CERTIFICATION TEST EXAM
2026 STUDY QUESTIONS WITH CORRECT
SOLUTIONS GUARANTEED PASS | RATED A+
A technician starts up a 5 year old natural gas furnace. The main burner lights and after 60
seconds the blower fan comes on, but the burner flames wavers in one corner. The technician
suspects - Answer>>> A faulty heat exchanger
Metal ductwork tends to transmit noise and fan vibrations to conditioned spaces in residential
installations. What type of connectors are specified to control this - Answer>>> Flex connectors
You have installed a Category IV two-pipe vent system that terminates through the roof of the
residence. The elbow for the combustion air intake, above the roof, should - Answer>>> Point it
down
A technician servicing an LP gas furnace notices a tag stating it was converted from natural gas.
He finds large amount of soot I'm the heat exchanger. What could be the cause of this soot -
Answer>>> Orifice, (spud) too large
A customer tells a technician that his six month old furnace stops heating before the residence is
warm. This happens only on very cold nights. The technician suspects - Answer>>> Incorrect
heat anticipatory setting
The reason heating thermostat have anticipated is to - Answer>>> Reduce lag
If the exact amount of air is supplied and perfect combustion occurs, in a natural gas furnace, a
specific percentage of CO2 content will be present in the flue gases. What percentage will be
present - Answer>>> 2% to 5.5%
When a Category IV LP unit is properly installed and operating normally with 50% excess air,
the CO2 content of the exhaust gases is - Answer>>> 10% to 14%
A gas furnace is to be installed in a garage. The national standards require that the burners and
ignition sources must be located ______ above the floor - Answer>>> 18 inches
The typical flue gas temperature of a Category III furnace is - Answer>>> 280°F - 300°F
TEST EXAM 2026 STUDY QUESTIONS
WITH CORRECT SOLUTIONS
GUARANTEED PASS | RATED A+
, HVAC 105 GAS HEAT CERTIFICATION TEST EXAM
2026 STUDY QUESTIONS WITH CORRECT
SOLUTIONS GUARANTEED PASS | RATED A+
A technician starts up a 5 year old natural gas furnace. The main burner lights and after 60
seconds the blower fan comes on, but the burner flames wavers in one corner. The technician
suspects - Answer>>> A faulty heat exchanger
Metal ductwork tends to transmit noise and fan vibrations to conditioned spaces in residential
installations. What type of connectors are specified to control this - Answer>>> Flex connectors
You have installed a Category IV two-pipe vent system that terminates through the roof of the
residence. The elbow for the combustion air intake, above the roof, should - Answer>>> Point it
down
A technician servicing an LP gas furnace notices a tag stating it was converted from natural gas.
He finds large amount of soot I'm the heat exchanger. What could be the cause of this soot -
Answer>>> Orifice, (spud) too large
A customer tells a technician that his six month old furnace stops heating before the residence is
warm. This happens only on very cold nights. The technician suspects - Answer>>> Incorrect
heat anticipatory setting
The reason heating thermostat have anticipated is to - Answer>>> Reduce lag
If the exact amount of air is supplied and perfect combustion occurs, in a natural gas furnace, a
specific percentage of CO2 content will be present in the flue gases. What percentage will be
present - Answer>>> 2% to 5.5%
When a Category IV LP unit is properly installed and operating normally with 50% excess air,
the CO2 content of the exhaust gases is - Answer>>> 10% to 14%
A gas furnace is to be installed in a garage. The national standards require that the burners and
ignition sources must be located ______ above the floor - Answer>>> 18 inches
The typical flue gas temperature of a Category III furnace is - Answer>>> 280°F - 300°F
