NATE GAS & HEAT NEWEST EXAM / NATE GAS & HEAT
PREPARATION/NATE GAS & HEAT EXAM PRACTICE EXAM WITH
150 QUESTIONS AND CORRECT ANSWERS| BRAND NEW
VERSION!
In order to achieve complete combustion with natural gas, each cubic foot of gas
must combine with no less than ______ cubic feet of air with an additional 5 cubic
feet of extra air to ensure there is enough oxygen for complete combustion.
A: 5 cubic feet
B: 10 cubic feet
C: 15 cubic feet
D: 20 cubic feet - Correct Answer-B: 10 cubic feet
The three elements of combustion are:
A: Fuel, oxygen and ignition
B: Nitrogen, oxygen and heat
C: Air, fuel and oxygen
D: Air, fuel and nitrogen - Correct Answer-A: Fuel, oxygen and ignition
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, NATE Gas & Heat Newest Exam / NATE Gas & Heat Preparation
Which of the following is a natural result of combustion?
A: Water vapor
B: Carbon monoxide
C: Carbon dioxide
D: All of the above - Correct Answer-D: All of the above
Primary air is air that:
A: Is mixed with the fuel before the fuel reaches the burner
B: Is mixed with the fuel at the burner after the fuel has ignited
C: Remains unused after the combustion process is complete
D: Enters the draft diverter and goes up the stack with the products of
combustion - Correct Answer-A: Is mixed with the fuel before the fuel reaches the
burner
Secondary air is air that:
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, NATE Gas & Heat Newest Exam / NATE Gas & Heat Preparation
A: Is mixed with the fuel before the fuel reaches the burner
B: Is mixed with the fuel at the burner after the fuel has ignited
C: Remains unused after the combustion process is complete
D: Enters the draft diverter and goes up the stack with the products of
combustion - Correct Answer-B: Is mixed with the fuel at the burner after the fuel
has ignited
The three major furnace configurations are:
A: Up-flow, down-flow and lowboy
B: Up-flow, down-flow and horizontal
C: Up-flow, down-flow and cross-flow
D: None of these is correct - Correct Answer-B: Up-flow, down-flow and horizontal
Residential gas furnaces use blowers powered by which types of motors?
A: Poly-phase, two phase, single phase and capacitor start
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, NATE Gas & Heat Newest Exam / NATE Gas & Heat Preparation
B: Shaded pole, split-phase, capacitor start and PSC
C: Three phase, shaded pole and PSC
D: Split-phase, induction start-induction run and variable speed DC - Correct
Answer-D: Split-phase, induction start-induction run and variable speed DC
Since 1992, the United States Department of Energy has required that all furnaces
sold and installed from that date on must have an AFUE of no less than:
A: 70%
B: 75%
C: 78%
D: 80% - Correct Answer-C: 78%
Many pre-1992 furnaces have efficiencies around _______.
A: 10%
B: 40%
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