PLUMBING (C-36) PRACTICE EXAMS
WITH CORRECT QUESTIONS AND
ANSWERS 2025
The boiling points at 0 degrees gas pressure in Fahrenheit are: Ammonia (NH3): -
CORRECT-ANSWERS28.0 degrees
Carbon dioxide (C2H5CO2): - CORRECT-ANSWERS110.50 degrees
Ethyl Chloride (C2H5CL) - CORRECT-ANSWERS55.6 degrees
Freon (F-12) (CC12F2) - CORRECT-ANSWERS21.7 degrees
One pound of pressure per sq. in. of water equals ______ feet of water at 62 degrees F. -
CORRECT-ANSWERS2.31
(Note: 1..433 = 2.31)
(Note: 1..31 = 0.433)
One foot of water at 62 degrees F equals ________ pounds pressure per square inch. -
CORRECT-ANSWERS0.433
,(Note: 1..31 = 0.433)
(Note: 1..433 = 2.31)
Sulfur Dioxide (SO2) - CORRECT-ANSWERS14.0 degrees
Methyl Chloride (CH3CL) - CORRECT-ANSWERS10.6 degrees
Freezol (iso-butane) (CH3) (3CH) - CORRECT-ANSWERS10.0 degrees
What is the minimum size water softener that may be used for a one inch water line in
order to prevent pressure drop? - CORRECT-ANSWERS27,000 grains per regeneration
cycle
Gas pressures for gas systems vary widely. What is the working pressure normally used
on hot water heaters installed at individual houses. - CORRECT-ANSWERS4 ounces
(~7 IWC)
No more than ______ cu. ft. of fuel gas or ______ lbs. of liquefied petroleum gas may be
stored inside. - CORRECT-ANSWERS2,000 - 300
What type of valve is used to shut off the main from the service? - CORRECT-
ANSWERSSlotted plug core shut off valve
,A gas vent connector shall have a continuous rise from the appliance to the vent of not
less than ____ per foot of length. - CORRECT-ANSWERS5"
The size of the supply piping outlet for any gas appliance shall be not less than: -
CORRECT-ANSWERS1/2".
What is the specific gravity of natural gas? - CORRECT-ANSWERS-66
A single-wall metal flue pipe installed to serve a gas fired water heater is required by
code to have a min. clearance of _____ inches from any combustible type materials. -
CORRECT-ANSWERS6
The melting point of propane is _______ degrees C. and the boiling point of propane is
_______ degrees C. - CORRECT-ANSWERS188 - 40
The melting point of butane is _______ degrees C. and the boiling point of butane is
_______ degrees C. - CORRECT-ANSWERS138 - 0.0
Low pressure gas piping 1/2" is installed to convey gas at pressure not to exceed a
water column of: - CORRECT-ANSWERS14".
, Mechanical ventilation must be provided when welding or cutting is done where there is
less than ______ cu. ft. of air per welder, where the ceiling is less than ____ ft. high, or
when working in confined quarters. - CORRECT-ANSWERS10,000 - 16
Earthquake security straps for a hot water heater shall be installed _____ from the top of
the tank and ____ from the bottom. - CORRECT-ANSWERS9"- 4"
Placement of safety valves on a boiler is on the: - CORRECT-ANSWERStop of boiler.
The size of the gas supply piping outlet for a recessed oven cannot be less than: -
CORRECT-ANSWERS1/2".
Oxygen cylinders must be stored at least ____ ft. from fuel gas cylinders or combustible
materials. - CORRECT-ANSWERS20
The minimum size strap for a hot water heater is: - CORRECT-ANSWERS1-1/2"-16
gauge.
The maximum distance from a gas appliance that the shut off valve may be is: -
CORRECT-ANSWERS3 feet.
WITH CORRECT QUESTIONS AND
ANSWERS 2025
The boiling points at 0 degrees gas pressure in Fahrenheit are: Ammonia (NH3): -
CORRECT-ANSWERS28.0 degrees
Carbon dioxide (C2H5CO2): - CORRECT-ANSWERS110.50 degrees
Ethyl Chloride (C2H5CL) - CORRECT-ANSWERS55.6 degrees
Freon (F-12) (CC12F2) - CORRECT-ANSWERS21.7 degrees
One pound of pressure per sq. in. of water equals ______ feet of water at 62 degrees F. -
CORRECT-ANSWERS2.31
(Note: 1..433 = 2.31)
(Note: 1..31 = 0.433)
One foot of water at 62 degrees F equals ________ pounds pressure per square inch. -
CORRECT-ANSWERS0.433
,(Note: 1..31 = 0.433)
(Note: 1..433 = 2.31)
Sulfur Dioxide (SO2) - CORRECT-ANSWERS14.0 degrees
Methyl Chloride (CH3CL) - CORRECT-ANSWERS10.6 degrees
Freezol (iso-butane) (CH3) (3CH) - CORRECT-ANSWERS10.0 degrees
What is the minimum size water softener that may be used for a one inch water line in
order to prevent pressure drop? - CORRECT-ANSWERS27,000 grains per regeneration
cycle
Gas pressures for gas systems vary widely. What is the working pressure normally used
on hot water heaters installed at individual houses. - CORRECT-ANSWERS4 ounces
(~7 IWC)
No more than ______ cu. ft. of fuel gas or ______ lbs. of liquefied petroleum gas may be
stored inside. - CORRECT-ANSWERS2,000 - 300
What type of valve is used to shut off the main from the service? - CORRECT-
ANSWERSSlotted plug core shut off valve
,A gas vent connector shall have a continuous rise from the appliance to the vent of not
less than ____ per foot of length. - CORRECT-ANSWERS5"
The size of the supply piping outlet for any gas appliance shall be not less than: -
CORRECT-ANSWERS1/2".
What is the specific gravity of natural gas? - CORRECT-ANSWERS-66
A single-wall metal flue pipe installed to serve a gas fired water heater is required by
code to have a min. clearance of _____ inches from any combustible type materials. -
CORRECT-ANSWERS6
The melting point of propane is _______ degrees C. and the boiling point of propane is
_______ degrees C. - CORRECT-ANSWERS188 - 40
The melting point of butane is _______ degrees C. and the boiling point of butane is
_______ degrees C. - CORRECT-ANSWERS138 - 0.0
Low pressure gas piping 1/2" is installed to convey gas at pressure not to exceed a
water column of: - CORRECT-ANSWERS14".
, Mechanical ventilation must be provided when welding or cutting is done where there is
less than ______ cu. ft. of air per welder, where the ceiling is less than ____ ft. high, or
when working in confined quarters. - CORRECT-ANSWERS10,000 - 16
Earthquake security straps for a hot water heater shall be installed _____ from the top of
the tank and ____ from the bottom. - CORRECT-ANSWERS9"- 4"
Placement of safety valves on a boiler is on the: - CORRECT-ANSWERStop of boiler.
The size of the gas supply piping outlet for a recessed oven cannot be less than: -
CORRECT-ANSWERS1/2".
Oxygen cylinders must be stored at least ____ ft. from fuel gas cylinders or combustible
materials. - CORRECT-ANSWERS20
The minimum size strap for a hot water heater is: - CORRECT-ANSWERS1-1/2"-16
gauge.
The maximum distance from a gas appliance that the shut off valve may be is: -
CORRECT-ANSWERS3 feet.
