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Question 1

What is the definition of a type A building?

Answer 1

Any building that is constructed airtight

Question 2

What is the only gas fired appliance that may be installed without the need of any outside air?

Answer 2

A water heater with an input not exceeding 50MBH and is the only gas appliance in the room or building

Question 3

When calculating the size of an opening from the building structure into the mechanical room how many BTU’s are required per square inch?

Answer 3

1000 BTU of appliance input per square inch for the opening

Question 4

When cutting an opening between the building structure and the mechanical room what measurements must you comply to?

Answer 4

Min 6” off the floor
Max 18” high
Maximum opening of 12” tall

Question 5

When installing a combustion air pot where must it be installed?

Answer 5

Within 1 foot above and two feet horizontally of the appliance having the largest BTU input

Question 6

A square or rectangular-shaped duct shall only be used when the required free area of the air-supply opening is ___ inches squared or larger, and when used, its smaller dimension shall not be less than ___ inches

Answer 6

9 inches squared

3 inches

Question 7

The minimum height an outdoor air supply must be installed is?

Answer 7

1 foot(12 inches)(300mm)

Question 8

How far away from a dryer hood must an outdoor air supply be installed?

Answer 8

3 feet

Question 9

What is required in conjunction with an outdoor air supply when the total input of the appliances is over 400 MBH?

Answer 9

A second opening must be installed high on the wall of the room to allow heat and spilled products of combustion to escape

Question 10

How do you calculate the ventilation opening high on the wall when the total input of the appliances on the room exceeds 400MBH?

How far away from the combustion air supply must it be?

Answer 10

Must be 10% of the area of the outdoor air supply opening but never smaller than 10 inches squared

12” away from combustion air

Question 11

When installing appliances WITH draft control decides (fan assist) how do you size the air supply opening?

Answer 11

Over 400MBH up to and including 1MMBH = 1 inch squared of opening for every 7000 BTU

OVEE 1MMBH = Use formula above + an additional 1 inch squared for each 14000 BTU over 1 MMBH

Question 12

When installing appliances WITHOUT draft control devices (natural draft) how do you calculate the size of the air supply opening?

Answer 12

All inputs over 400MBH require 1 inch squared for every 30000 BTU

Question 13

When both fan assist and natural draft appliances are installed, how do you size the air supply opening?

Answer 13

The air supply opening is calculated for each type then added together

Question 14

How do you calculate grille size?

Answer 14

The area of the grills bars or slats is subtracted from the area of the opening

Question 15

What is the smallest allowable dimension of an opening in a grille or louvre?

Answer 15

1/4”

Question 16

Can you use manual dampers or louvres on an air supply?

Answer 16

No

Question 17

What must be done when using an automatic louvre or dampener?

Answer 17

Must be interlocked with the appliance so that the appliance will not fire when the dampener or louvre is in the closed position

Question 18

What is the maximum length of an air supply duct before it must be upsized?

What is the maximum length an air supply duct must not exceed?

Answer 18

20 feet

50 feet

Question 19

How do you size an air supply duct that exceeds 20 feet but is less than 50 feet?

Answer 19

Upsize it one pipe size

Question 20

How many equivalent feet of pipe does a sheet medal adjustable 90° elbow account for?

Answer 20

10’