C20 Practice Test 2 Exam Questions and
Answers Graded A+
What is the correct type of seam for a grease stop?
Pittsburgh lock
S cleat
welded continuously on outside
spot welded on inside - Correct answer-welded continuously on outside
Type-B vents are recommended for:
incinerators
combination gas-oil appliances
appliances convertible to solid fuel
standard gas-fired furnaces - Correct answer-standard gas-fired furnaces
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,Cranes with a boom longer than 60 ft or with a rating greater than _____ require a
boom-angle indicator.
5 tons
10 tons
15 tons
20 tons - Correct answer-15 tons
A pressure control responds to:
refrigerant temperature
condenser pressure
expansion valve
suction and discharge pressure - Correct answer-suction and discharge pressure
The registers for a gravity-type furnace should be located:
in the floor
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,in the ceiling
high on the wall
low on the wall - Correct answer-in the floor
What happens when a refrigerant (e.g., Freon-12) is exposed to air and a flame?
explosion
a poisonous gas is produced
condensation
none of the above - Correct answer-a poisonous gas is produced
Uninsulated furnace flue pipes should have a minimum clearance of _____ from
any combustible materials.
6 in
12 in
18 in
24 in - Correct answer-6 in
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, What gage metal should a 30" x 10" sheet metal duct be made from? - Correct
answer-24
The unobstructed total area of air-supply ducts from a gravity warm-air furnace
with an output rating of 64,000 Btu/h must be at least:
128 sq in
256 sq in
384 sq in
448 sq in - Correct answer-448 sq in
What would cause a gas furnace to expel black soot?
too much fuel
not enough air
clogged flue
both A and B - Correct answer-both A and B
The safety valve on a portable air compressor should be popped at least: - Correct
answer-weekly
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Answers Graded A+
What is the correct type of seam for a grease stop?
Pittsburgh lock
S cleat
welded continuously on outside
spot welded on inside - Correct answer-welded continuously on outside
Type-B vents are recommended for:
incinerators
combination gas-oil appliances
appliances convertible to solid fuel
standard gas-fired furnaces - Correct answer-standard gas-fired furnaces
©COPYRIGHT 2025, ALL RIGHTS RESERVED 1
,Cranes with a boom longer than 60 ft or with a rating greater than _____ require a
boom-angle indicator.
5 tons
10 tons
15 tons
20 tons - Correct answer-15 tons
A pressure control responds to:
refrigerant temperature
condenser pressure
expansion valve
suction and discharge pressure - Correct answer-suction and discharge pressure
The registers for a gravity-type furnace should be located:
in the floor
©COPYRIGHT 2025, ALL RIGHTS RESERVED 2
,in the ceiling
high on the wall
low on the wall - Correct answer-in the floor
What happens when a refrigerant (e.g., Freon-12) is exposed to air and a flame?
explosion
a poisonous gas is produced
condensation
none of the above - Correct answer-a poisonous gas is produced
Uninsulated furnace flue pipes should have a minimum clearance of _____ from
any combustible materials.
6 in
12 in
18 in
24 in - Correct answer-6 in
©COPYRIGHT 2025, ALL RIGHTS RESERVED 3
, What gage metal should a 30" x 10" sheet metal duct be made from? - Correct
answer-24
The unobstructed total area of air-supply ducts from a gravity warm-air furnace
with an output rating of 64,000 Btu/h must be at least:
128 sq in
256 sq in
384 sq in
448 sq in - Correct answer-448 sq in
What would cause a gas furnace to expel black soot?
too much fuel
not enough air
clogged flue
both A and B - Correct answer-both A and B
The safety valve on a portable air compressor should be popped at least: - Correct
answer-weekly
©COPYRIGHT 2025, ALL RIGHTS RESERVED 4
