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66 Cards in this Set
- Front
- Back
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Pilot that is lit each time there is a call for heat and continues to function until call for heat ends? |
Intermittent pilot minu |
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Minimum flame to ground area that is immersed in the flame? |
1:4 |
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What would you select on the electrical meter to read the flame signal? |
DC microamps |
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How do you size an air supply duct having draft hood appliance and a fan assisted? |
Size the draft on 8.1 Size draft and fan on 8.2 Pick the largest size between the two charts |
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Threaded schedule 40 steel piping may be used for pressures not exceeding? |
125 PSI |
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A 2 1/2" NPS welded gas line shall be tested at what and how long? |
50 psi or 1.5 tines working pressure for 180 minutes. |
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A gas line 4" or larger that has been tested with air must be purged with what? |
Nitrogen or carbon dioxide |
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How many wraps on gas pipe with teflon tape? |
1 1/2 wraps (50% overlap) |
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Minimum rated pressure on a hose is? |
350 psi |
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Max length of permanent hose is? |
10 feet |
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Construction hose is? |
15'-75' |
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Max length of portable appliance hose? |
30 feet |
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Class 300 fitting has max pressure if what? |
300 psi |
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How many wraps on gas pipe with teflon tape? |
1 1/2 wraps (50% overlap) |
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Minimum rated pressure on a hose is? |
350 psi |
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Max length of permanent hose is? |
10 feet |
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Construction hose is? |
15'-75' |
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Max length of portable appliance hose? |
30 feet |
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Max length of flex connector on a vented appliance? |
2 feet |
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Max length of a flex connector on unvented appliance? |
6 feet |
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When a pipe protrudes thru a floor how much unthreaded pipe must be exposed? |
2" |
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Class 300 fitting has max pressure if what? |
300 psi |
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How many wraps on gas pipe with teflon tape? |
1 1/2 wraps (50% overlap) |
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Minimum rated pressure on a hose is? |
350 psi |
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Max length of permanent hose is? |
10 feet |
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Construction hose is? |
15'-75' |
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Max length of portable appliance hose? |
30 feet |
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Max length of flex connector on a vented appliance? |
2 feet |
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Max length of a flex connector on unvented appliance? |
6 feet |
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When a pipe protrudes through a wall how much unthreaded pipe must be exposed? |
1" |
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Gas pressures above 125 psi require what pressure rating? |
Fittings rated for 250 psi |
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What type of meter is used to measure flow? |
Ammeter |
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What does it mean when a digital meter flashes the display? |
The value has exceeded the meter setting. |
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An ammeter is connected to a circuit, but the circuits fuse keeps burning out. What is problem? |
The meter is connected to the load in parallel |
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How is a module reset once it has locked out? |
The power to module is shut off and then turned back on |
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On a direct spark ignition (DSI) what happens after the module conducts the safe start check? |
The spark and the main burner gas are turned on. |
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What is the purpose of the safe start check performed by the module? |
Ensure module doesn't sense false flame |
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What device proves the induced draft fan is moving air? |
Pressure switch |
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What is the main difference between an intermittent pilot gas valve and a direct spark ignition (DSI) gas valve? |
DSI gas valve has no pilot connection |
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Why have the flame conductivity systems not been used for proving the flame? |
The system will not distinguish between a flame and short to the ground |
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Which portion of air supply is used to tune the burner? |
Excess air |
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Which type of fuel has a hydrogen/carbon ratio? |
Propane |
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How much of the air is oxygen? |
20% |
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Where should the flue gas sample be taken from? |
In combustion chamber upstream of draft control |
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What would cause the burner flame to become unstable when the circulating air blow is activated? |
Cracks or holes in heat exchanger |
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What would cause the burner flame to become unstable when the circulating air blow is activated? |
Cracks or holes in heat exchanger |
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How do you get perfect combustion? |
Low excess air, low stack, high co2 |
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What would cause the burner flame to become unstable when the circulating air blow is activated? |
Cracks or holes in heat exchanger |
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How do you get perfect combustion? |
Low excess air, low stack, high co2 |
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What appliance is most likely to be a direct vent? |
Fireplace |
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What is the minimum distance between a building opening and the vent terminal of a direct vent appliance with an input of 58 MBH? |
12" |
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Besides being fully open on a minimum of two sides, what other code requirement must be met when terminating a vent under a deck? |
Deck must be at least 12" above the vent |
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Besides being fully open on a minimum of two sides, what other code requirement must be met when terminating a vent under a deck? |
Deck must be at least 12" above the vent |
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What is minimum distance between a direct vent terminal and ground level? |
12" |
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What is the minimum required fixed opening when an automatic damper is installed on an appliance? |
20 % |
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How often should commercial tubing be identified? |
Every 20 feet |
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How often should a 3" horizontal gas line be supported? |
Every 15 feet |
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Where should you install the vents on regulators? |
On the vertical plane, pointing down |
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How far must vent termination be from moisture exhaust duct? |
3 feet |
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How far must vent terminate from mechanical intake? |
10 feet |
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A corrugated metal connector shall not exceed 2' when connecting what? |
Suspended appliance or decorative appliance |
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Where should you install the vents on regulators? |
On the vertical plane, pointing down |
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How far must vent termination be from moisture exhaust duct? |
3 feet |
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How far must vent terminate from mechanical intake? |
10 feet |
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A corrugated metal connector shall not exceed 2' when connecting what? |
Suspended appliance or decorative appliance |
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On a propane 2-psi system, the system regulator must be within what distance of exterior wall? |
3 feet |
