Propane and Natural Gas Exam 2023 Questions and
Answers 100% Verified
If an appliance cannot be converted to another fuel ex. propane to natural gas, it
must be a ___ appliance
"Dedicated" Appliance
The "10ft-2ft-3ft" rule is a reference to what?
It means that chimneys must be 3ft above the highest point of where it passes through,
while still being 2ft higher than any portion of roof within 10ft
How many feet must a type B or L vent terminate, at minimum, above the highest
connected appliance draft hood or flue collar?
5 feet
A gas vent (B or L) must terminate atleast ___ft above a forced air inlet located
within ___ft
A gas vent (B or L) must terminate at least 3ft above a forced air inlet located within 10ft
Two ways CSST or copper tubing can be installed inside hollow walls or
partitions if it is concealed?
1) Installed in single runs that are not rigidly secured
2) With steel striker barrier, minimum 16 gauge*, barrier extends 4"
*1.3mm or .0508" thick
What is the minimum pressure for a pressure test?
1 1/2 times max working pressure, never less than 3 psi
What is the minimum duration for a pressure test?
10 minutes
What is the chemical formula of propane?
C3H8
What is the specific gravity of liquid propane?
.504
What is the specific gravity of vapor propane?
1.50
What is the boiling point of propane?
-44 F
What is the ignition temperature of propane?
920 F
What is the upper flammability limit of propane?
9.60%
What is the lower flammability limit of propane?
2.15%
What is the combustion ratio of propane?
24 to 1
How many BTU per cubic foot of propane vapor?
2488 btu
How many BTU per gallon of propane?
,91,502 btu
What is the chemical formula of natural gas?
CH4
What is the specific gravity of liquid natural gas?
.30
What is the specific gravity of natural gas vapor?
.60
What is the boiling point of natural gas?
-260 F
What is the ignition temperature of natural gas?
1,150 F
What is the upper limit of natural gas?
14%
What is the lower limit of natural gas?
4%
What is the ideal combustion ratio natural gas?
10 to 1
How many BTU per cubic foot of natural gas?
1000 btu
What is a furnace plenum?
A chamber constructed of duct work attached to inlet or outlet of furnace with one or
more ducts connected to it
A drip (leg) is placed where and to collect what?
A drip (leg) is placed at the lowest point of system piping, in order to collect condensate
(which can then be removed), should not be placed where condensate could freeze
*Also at outlet of meter in some cases
Which device would turn on or off an appliance's gas supply in response to
changes in pressure, temperature, or liquid level?
A limit control
Condensate separates from flue gas due to either a reduction of ___ or an
increase in ___
Condensate is created either through a reduction of temperature or an increase in
pressure
What is the difference between a type 1 and type 2 clothes dryer?
A type 1 dryer is for family living
A type 2 dryer is for business/public
What is a BTU?
British Thermal Unit, quantity of heat needed to raise 1 pound of water 1 degree
fahrenheit
What are the maximum temperature and pressure in a low pressure water boiler?
A low pressure water boiler has a maximum water temperature of 250 F and pressure of
160 psi
What are the maximum pressure in a low pressure steam boiler?
15 psi
, Two characteristics of a Category IV Vented Appliance?
1) Positive Pressure
2) Excessive Condensate
Two characteristics of a Category III Vented Appliance?
1) Positive Pressure
2) AVOIDS Excessive Condensate
Two characteristics of a Category I Vented Appliance?
1) NON Positive Pressure
2) AVOIDS Excessive Condensate
What is the difference between accessible and readily accessible?
Accessible requires removal of panel WHILE readily accessible means no panel
Where must a sediment trap be installed, what is it made of, and what is the
minimum length?
A sediment trap is located downstream of an appliance shut off,
it is made of a capped nipple off a tee,
at a minimum length of 3 inches
If the height of a passageway is less than 6 feet tall, the distance from
passageway to appliance is maximum...
20 feet
What is the minimum amount of cover for an underground piping system? And
what is an exception?
The minimum amount of cover is 12 inches
An exception is if there is a likely possibility of external damage, 18 inches is the
minimum cover
Why can't a 4 inch draft hood be reduced to a 3 inch vent?
Because in order to reduce vent size, the draft hood must be more than 4 inches
If a draft hood outlet or flue collar is 12 inches or more, what is the maximum
number of sizes a vent can be reduced?
2 sizes
If a draft hood outlet or flue collar is 12 inches or less, what is the maximum
number of sizes a vent can be reduced?
1 size
What is the maximum BTU for an unvented room heater in a bathroom?
6,000 btu
What is the maximum BTU for an unvented room heater in a bedroom?
10,000 btu
What is the minimum dimension of an attic opening/pathway?
22" X 30" but larger than largest part of appliance
Which two types of appliances are not factored into an appliance air calculation?
Direct vent appliances and clothes dryers
Answers 100% Verified
If an appliance cannot be converted to another fuel ex. propane to natural gas, it
must be a ___ appliance
"Dedicated" Appliance
The "10ft-2ft-3ft" rule is a reference to what?
It means that chimneys must be 3ft above the highest point of where it passes through,
while still being 2ft higher than any portion of roof within 10ft
How many feet must a type B or L vent terminate, at minimum, above the highest
connected appliance draft hood or flue collar?
5 feet
A gas vent (B or L) must terminate atleast ___ft above a forced air inlet located
within ___ft
A gas vent (B or L) must terminate at least 3ft above a forced air inlet located within 10ft
Two ways CSST or copper tubing can be installed inside hollow walls or
partitions if it is concealed?
1) Installed in single runs that are not rigidly secured
2) With steel striker barrier, minimum 16 gauge*, barrier extends 4"
*1.3mm or .0508" thick
What is the minimum pressure for a pressure test?
1 1/2 times max working pressure, never less than 3 psi
What is the minimum duration for a pressure test?
10 minutes
What is the chemical formula of propane?
C3H8
What is the specific gravity of liquid propane?
.504
What is the specific gravity of vapor propane?
1.50
What is the boiling point of propane?
-44 F
What is the ignition temperature of propane?
920 F
What is the upper flammability limit of propane?
9.60%
What is the lower flammability limit of propane?
2.15%
What is the combustion ratio of propane?
24 to 1
How many BTU per cubic foot of propane vapor?
2488 btu
How many BTU per gallon of propane?
,91,502 btu
What is the chemical formula of natural gas?
CH4
What is the specific gravity of liquid natural gas?
.30
What is the specific gravity of natural gas vapor?
.60
What is the boiling point of natural gas?
-260 F
What is the ignition temperature of natural gas?
1,150 F
What is the upper limit of natural gas?
14%
What is the lower limit of natural gas?
4%
What is the ideal combustion ratio natural gas?
10 to 1
How many BTU per cubic foot of natural gas?
1000 btu
What is a furnace plenum?
A chamber constructed of duct work attached to inlet or outlet of furnace with one or
more ducts connected to it
A drip (leg) is placed where and to collect what?
A drip (leg) is placed at the lowest point of system piping, in order to collect condensate
(which can then be removed), should not be placed where condensate could freeze
*Also at outlet of meter in some cases
Which device would turn on or off an appliance's gas supply in response to
changes in pressure, temperature, or liquid level?
A limit control
Condensate separates from flue gas due to either a reduction of ___ or an
increase in ___
Condensate is created either through a reduction of temperature or an increase in
pressure
What is the difference between a type 1 and type 2 clothes dryer?
A type 1 dryer is for family living
A type 2 dryer is for business/public
What is a BTU?
British Thermal Unit, quantity of heat needed to raise 1 pound of water 1 degree
fahrenheit
What are the maximum temperature and pressure in a low pressure water boiler?
A low pressure water boiler has a maximum water temperature of 250 F and pressure of
160 psi
What are the maximum pressure in a low pressure steam boiler?
15 psi
, Two characteristics of a Category IV Vented Appliance?
1) Positive Pressure
2) Excessive Condensate
Two characteristics of a Category III Vented Appliance?
1) Positive Pressure
2) AVOIDS Excessive Condensate
Two characteristics of a Category I Vented Appliance?
1) NON Positive Pressure
2) AVOIDS Excessive Condensate
What is the difference between accessible and readily accessible?
Accessible requires removal of panel WHILE readily accessible means no panel
Where must a sediment trap be installed, what is it made of, and what is the
minimum length?
A sediment trap is located downstream of an appliance shut off,
it is made of a capped nipple off a tee,
at a minimum length of 3 inches
If the height of a passageway is less than 6 feet tall, the distance from
passageway to appliance is maximum...
20 feet
What is the minimum amount of cover for an underground piping system? And
what is an exception?
The minimum amount of cover is 12 inches
An exception is if there is a likely possibility of external damage, 18 inches is the
minimum cover
Why can't a 4 inch draft hood be reduced to a 3 inch vent?
Because in order to reduce vent size, the draft hood must be more than 4 inches
If a draft hood outlet or flue collar is 12 inches or more, what is the maximum
number of sizes a vent can be reduced?
2 sizes
If a draft hood outlet or flue collar is 12 inches or less, what is the maximum
number of sizes a vent can be reduced?
1 size
What is the maximum BTU for an unvented room heater in a bathroom?
6,000 btu
What is the maximum BTU for an unvented room heater in a bedroom?
10,000 btu
What is the minimum dimension of an attic opening/pathway?
22" X 30" but larger than largest part of appliance
Which two types of appliances are not factored into an appliance air calculation?
Direct vent appliances and clothes dryers
