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50 Cards in this Set
- Front
- Back
- 3rd side (hint)
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If flue gases are not vented properly, carbon monoxide poisoning could result. True or false? |
True |
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Liquefied petroleum is lighter than air and will not stay in pockets. True or false? |
False |
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a gas furnace designed for use with natural gas can be used with liquefied petroleum with no system modifications. True or false? |
False |
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A gas flame will carry electric current so it can be used to_______________. |
Prove the flame |
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In the USA, natural gas supplier supply gas with a heat content of about 1050 BTU per cu. Ft. True or False? |
True |
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The gas flame will lift off the burner and be noisy if it receives too little primary air. True or false? |
False |
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Another name for a downflow heating unit is______________. |
Counterflow |
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Spark ignition is important for roof top or package units located outdoors because of problems with? |
Wind |
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When a gas furnace ignites and is under "full fire", why does the fan not come on immediately? |
The chamber must warm up first |
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On a natural gas furnace the manifold pressure is set at? |
3.5 WC (Water colom) |
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when the burners ignite, the burner flame is normal until the blower starts. At this time, continuous roll out occurs. What is the problem? |
A crack in the heat exchanger |
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What type of burner is normally used for pilot flames? |
Bunsen burner |
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What safety would keep the furnace from operating if the combustion motor failed? |
Pressure switch |
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When the furnace continues to spark after the pilot is lit, what prevents the main burners from lighting? |
Flame sensor |
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What is the final step after the thermostat calls for heat? |
Indoor blower motor starts |
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The term 100% shuts off gas valve means: |
The gas is completely shut off to the unit for safety reasons |
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I'm working on a gas furnace what is the first thing to remember? |
That you're working with electricity and gas |
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Gas furnaces are not known to kill the occupants. |
False |
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When using a torch to braze A fitting, the technician should use the proper size___________, wear____________ and always have a __________________ near by. |
Torch tip, safety glasses and fire extinguisher. |
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To ensure proper operation of an oxygen cylinder regulator, make sure to oil it. True or false? |
False |
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Tube cutters are used to: |
Cut copper tubing |
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if a technician needed 5/8" ACR for an installation and only a plumbing supply house was located near, what size and type of pipe should he ask for? |
1/2 ID copper |
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The maximum temperature at which soft soldering is done is: |
800 degrees |
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Brazing is done at____________ soldering. |
Higher temperatures than |
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When soldering or brazing, the solder is: |
Melted by heat from the tubing and fitting |
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The proper type of flame from an oxy acetylene torch for silver brazing is: |
Neutral flame |
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Molten solder flows between the two base metals being soldered because: |
Capillary action |
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If there's too much primary air, the gas flame can: |
B & C |
Get blown out Lift off the burner |
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a furnace with a vertical air flow through the heat exchanger and the blower compartment located above the heat exchanger is called: |
Downflow |
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a furnace with a vertical air flow through the heat exchanger and the blower compartment located beneath the heat exchanger is called: |
Upflow |
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A furnace with a horizontal air flow through the heat exchanger and the blower compartment located on one end is called: |
Horizontal |
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The proper color of a gas flame is: |
A blue flame with a slightly orange tip |
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Primary air adjusters on atmospheric type gas burners are usually: |
Any of them |
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The orifice is a precisely sized hole in the: |
Spud |
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In a natural venting gas furnace, the hot flue gases are: |
Vented by natural convection |
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What is the function of the high limit switch on a gas furnace? |
It turns off burners if the heat exchanger becomes too hot |
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A hot surface ignitor is used to: |
A & B |
Ignite the main burner Ignite the pilot when thermostat calls for heat |
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The pressure switch on a gas furnace prevents the furnace from operating if the gas pressure is too low. True or false? |
False |
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A direct spark ignition (DSI) system is designed to: |
Ignite the main burner |
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A condensing gas furnace uses_____________ from a condensing type heat exchanger to increase the furnace efficiency. |
Latent heat |
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when tubing is cut with a tubing cutter, a burr is produced in the process. This slight decrease in the inside diameter of the tube cannot adversely affect the operation of the system. True or false? |
False |
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The copper phosphorus brazing alloy is good for connecting copper to___________ without needing flux. |
Copper |
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The use of flux is always required when soldering or brazing. True or false? |
False |
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What should the flow pressure for the oxygen regulator be set at? |
10psig |
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When soldering, the technician should heat the solder with a torch to allow it to melt. True or false? |
False |
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What should the flow pressure for the regulator be set at? |
5psig |
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Acetylene bottles are to be stored upright when transported. True or false? |
True |
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What is the first step when lighting an oxy acetylene torch? |
Check for flammable materials in the area to be brazed and that safe conditions are available. |
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What should the acetylene pressure never be allowed to go above? |
15psig |
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What is the first step after the thermostat calls for heat? |
Start the combustion blower |
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