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31 Cards in this Set
- Front
- Back
- 3rd side (hint)
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What type of efficiency is used to describe the overall efficiency of an appliance? |
Annual fuel utilization efficiency |
AFUE |
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How was efficiency of central heating appliances increased to mid-efficiency? |
The heat exchanger was redesigned |
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How is the efficiency of a furnace increased to the high-efficiency range? |
The water vapour in the flue gases is condensed |
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What is the main difference between a mid-efficient appliance and a high-efficient appliance? |
The high-efficient appliance condenses the water vapour in the flue gases |
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What device proves that the induced draft fan is moving air? |
The pressure switch |
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What category would an appliance with a draft hood be? |
Category 1 |
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What is the pressure in the vent serving an operating category 1 appliance? |
Non-positive |
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Which category of appliance condenses the water vapour in the flue gas? |
Category 4 |
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What type of vent would normally be used with a category 1 appliance? |
Type B vent |
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A forced draft burner utilizes a fan of sufficient size to: |
Overcome the restriction of the appliance and the burner |
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Where is the induction fan located on a fan assist appliance? |
At the flue outlet of the appliance |
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Before the gasfitter leaves any gas appliance they have worked on, they must ensure: |
Operating instructions, wiring diagrams are with the appliance . The appliance is operating safely under all rates of firing All safety and limit controls are operating normally |
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Which combustion chamber design is not suitable for conversion (solid/liquid to gas) |
Revertible |
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Who is responsible for instructing the customer on the safe operation of the appliance |
The installer of the appliance |
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What should you do with the manuals that are supplied with new appliances |
Turn them over to the owner of the appliance(so they can loose them lol) |
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What is required when an appliance has been damaged by fire or flood? |
Have the appliance inspected by an authorized agency |
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T/F: the combustion air prove switch is normally closed! |
False |
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An inspirated burner carries that name because: |
Most of the air for combustion is entrained with fuel prior to ignition |
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The major difference between a mid-efficient heat exchanger and a natural draft heat exchanger is? |
The resistance to the flow of the products of combustion through them |
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A mid-efficient furnace with staged firing:in nozzle |
Requires an induced draft fan which is capable of operating at different speeds |
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In nozzle mixing burners: |
The air and gas are kept separate throughout the burner and mixed at the outlet |
Torch |
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A blast burner: |
Is one of the simplest designs of nozzle burners |
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Burners are classified into two categories by the way: |
The fuel/air is supplied to the combustion chamber |
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Aspirated burners require: |
A forced draft fan |
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The fan of a power burner: |
Can be driven by fuel escaping from holes in the ends of the propeller-like blades |
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Burner ports for different burners: |
Are made with different methods and patterns for different applications and burner materials of manufacture |
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The heat exchanger of a mid-efficient appliance has restricted flow to:the induced k |
allow a high percentage of heat to be extracted from the products of combustion |
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The induced draft fan is used on mid-efficient appliances to: |
Draw the products of combustion through the heat exchanger |
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In shot burners have a deflector plate on their outlet so: |
The flame will not impinge on the back surface of the combustion chamber |
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Radiant surface tube heaters:an induced draft fan ach |
Often use reflector plates above them to reflect heat where needed |
To reflect heat |
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An induced draft fan achieves negative pressure in the venting system: |
Through the design of its discharge housing |
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