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42 Cards in this Set
- Front
- Back
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What is the minimum size of a square or rectangular air supply duct? |
9 square inches No dimension smaller than 3” |
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What is the minimum size of an opening used to ventilate the space containing appliances over 400 MBH? |
Atleast 10 square inches At least 10% of the combustion air area |
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When is ventilation air required? |
When the space containing appliances has a total input of over 400 MBH |
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What is the correct location of the terminus of an outdoor combustion air duct supplying less than 400 MBH? |
Within 1 foot above, and 2 feet horizontally of the burner of the appliance with the largest input |
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How far above ground level minimum must the inlet from outdoors for a combustion air duct be? |
12 inches |
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An appliance with a draft hood is installed in a mechanical room of a type B building. if a transfer Grille were used to supply combustion air to the enclosure from inside what formula would be used? |
One square inch for each 1000 BTUs |
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When air is supplied by Mechanical means what must be done? |
It must be interlocked with the appliance |
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When air supply from a structure into an enclosure containing draft hood, equipped appliances is installed a second opening is required. Where must the opening be located? |
As close as possible to the ceiling No lower than the lowest drafted opening |
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A ventilation air supply can be used to replace a combustion air supply. True or false |
False |
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An outdoor air supply shall not be required for a single water heater with an input of _______ btu/h or less when there are no other appliances that require an air supply |
50 000 btu/h |
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Where should the discharge of an outdoor air supply be located when the total input exceeds 400 MBH? |
Anywhere in the mechanical room, where it will not affect any water, steam or electrical equipment |
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What must be installed on the inlet of an outdoor combustion air opening? |
Sum means to prevent the direct entry of wind and rain |
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What is the smallest opening allowed in a screen or grill used for air supply? |
1/4 inch |
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What is the maximum equivalent length of duct allowed by table 8.1 before the size is increased? |
20 feet |
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According to the Alberta building code, what is the minimum size of fresh air duct required for a single-family home?(connected to the return air duct) |
4 inches in diameter |
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What must be done when the total equivalent Duct length exceeds 20 feet? |
The table size of the duct is increased one size |
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When the total input of the appliances in an enclosure exceeds 400 MBH where must the air supply duct originate? |
All air must be brought in from the outdoors |
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When the total input of an appliance in an enclosure exceeds 400 MBH what other requirements must be considered? |
The space containing the appliances must be ventilated |
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What formula would be used to size the air supply for a power burner equipped appliance? |
1 in.² for each 30,000 BTUs of input |
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Where must the combustion air pot be located when the total appliance input is less than 400 MBH? |
Within 1 foot above, and 2 feet away from the largest appliance burner |
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What is the minimum size of a ventilation air opening when the input exceeds 400 MBH? |
10 in.² |
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How is ventilation air for appliance installations over 400 MBH sized? |
It is sized at 10% of the air supply size but not smaller than 10 square inches |
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Where would the transfer grill be located? |
Between 6 inch an 18 inch above the floor |
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What is the minimum size of the fresh air intake and duct ? |
4 inch diameter |
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Loose construction is also called |
Type b building |
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Air tight construction building is also called |
Type A building |
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If you were unsure, if the building is tight or loose, which one would it be classified as? |
Air tight |
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Type A construction buildings, must acquire all of the air supply from where? |
Outside |
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Buildings that are type B construction, may acquire all the air supply from where? |
All indoor or all outdoor |
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Lengths exceeding 50 feet will require who to calculate the size? |
Mechanical engineer |
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Every 90 degree change adds how much to the overall length? |
10ft |
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if a length is over 20ft what must be done to the size of duct ? |
go with one size larger |
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if the length exceeds 50ft in length what needs to happen? |
it will need a mechanical air supply (fan) |
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draft hood appliances over 400 MBH require 2 grilles, where would they be located? |
minimum 6" from the floor and max 18" and the other as close to the ceiling as can be but no lower than the lowest drafthood |
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what category of appliance is high efficient, is direct vented and does not require air supply? |
Category IV |
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which category appliance draws air from inside the building to burn and needs a combustion air vent? |
category 1 |
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how far must an air supply be from a moisture exhaust duct? |
3ft |
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2 types of category 1 appliances what are they? |
1. Draft hood equipped appliance 2. Fan assisted appliance |
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what is the extra air called that is needed by a draft hood equipped appliance? |
dilution air |
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tight building is also known as what? |
Type A |
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Loose building is also known as what ? |
Type b |
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when there is draft hood appliance and a fan assisted appliance which steps do you take to size the ducts? |
1. take the btu load of the draft hood appliance to table 8.1 or (8.3 over 400mbh) 2. take the btu load of both appliances to table 8.2 or( 8.4 over 400mbh) 3. choose the largest duct size of the 2 |
