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160 Cards in this Set
- Front
- Back
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Which of the following is not a piece of heating equipment?
a) convector b) radiator c) steam d) unit heater e) fin coil |
c) steam |
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When air is forced through a heating coil, where the fan and coil are within the same unit, the unit is known as:
a) a unit heater b) an injector c) a diverter d) an air vent e) a converter |
a) a unit heater |
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The amount of air passing through the unit ventilator can be controlled by:
a) three-speed switches b) automatic valves c) traps d) air vents e) supply ducts |
a) three-speed switches |
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Unit heaters differ from convectors in that they use __________ to increase heat transfer.
a) metal fins b) natural circulation c) blowers d) copper tubes e) brass tubes |
c) blowers |
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The packless radiator valve has a __________ that completely seals off the valve body.
a) disk b) packing c) diaphragm d) spring e) stem |
c) diaphragm |
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The device which allows condensate to drain from a steam heater but stops the steam from escaping is called a:
a) radiator b) convector c) air vent d) radiator trap e) air separator |
d) radiator trap |
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Another name for a unit ventilator is a:
a) radiator b) exhauster c) convector d) register e) univent |
e) univent |
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Unit ventilators use:
a) only outside air for heating b) only inside air for heating c) natural draft d) a mixture of inside and outside air e) fin coil heaters |
d) a mixture of inside and outside air |
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The level in the condensate receiver is automatically controlled by a:
a) float switch b) pressure reducing valve c) gate valve d) drain valve e) sight glass |
a) float switch |
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__________ have largely replaced the cast-iron radiator in modern installations.
a) unit heaters b) radiator traps c) convectors d) open heaters e) space heaters |
c) convectors |
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A radiator trap is a device that is used to:
a) allow only air to leave the radiator b) vent steam from the radiator c) depressurize a radiator d) allow only steam to leave the radiator e) allow only water to leave the radiator |
e) allow only water to leave the radiator |
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The vacuum pump performs the following function:
a) supplies water to the condensate receiver b) supplies steam to the boiler c) returns the condensate (water) back to the boiler d) returns the condensate water to the condensate receiver e) returns the condensate vapour to the Deaerator |
c) returns the condensate (water) back to the boiler |
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Air can be removed from steam heating systems by:
a) air vents b) a steam trap c) an air separator d) an air header e) a dip tube |
a) air vents |
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Push nipples are:
a) devices used to connect radiator sections together b) air release devices on radiators c) greasing devices for furnace fans d) a connection used for pressure gauges e) used to connect pipes together in a heating system |
a) devices used to connect radiator sections together |
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The difference between a convector and an older type radiator is:
a) the way they transfer heat b) the way the heating medium goes through c) the method of control d) that one is made of cast iron and the other of steel or copper e) the way the heating and cooling is distributed |
d) that one is made of cast iron and the other of steel or copper |
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In fin coil type heaters, individual room temperature is controlled by:
a) switched b) automatic valves c) dampers d) air relays e) supply ducts |
c) dampers |
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A frequent means of heating large facilities such as factories, warehouses and garages, is to use a:
a) fin fan b) space heater c) convector d) radiator e) unit heater |
e) unit heater |
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In a __________ system, the mains are located above the heating units.
a) wet b) dry c) upfeed d) downfeed e) return feed |
d) downfeed |
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When starting up a steam boiler it should be filled to:
a) the maximum level b) 3/4 of a gauge glass c) 1/2 of a gauge glass d) 1/4 of a gauge glass e) the lowest visible part of the gauge glass |
c) 1/2 of a gauge glass |
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The return trap must be mounted at least _________ cm above the waterline in the boiler.
a) 100 b) 45 c) 30 d) 25 e) 15 |
b) 45 |
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All supply and drain lines of a steam heating system must be pitched to:
a) allow for drainage of condensate b) allow collection of air at the highest points c) prevent corrosion d) allow for temperature expansion e) allow for ease of instillation |
a) allow for drainage of condensate |
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The cause for any cold section in a steam heating system may be: (choose all that apply)
[a] a closed valve [b] a broken valve spindle [c] a defective trap [d] a defective air valve [e] too much steam flow |
[a] a closed valve [b] a broken valve spindle [c] a defective trap [d] a defective air valve |
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Regarding the "two-pipe with variable vacuum" steam heating system, in the sub-atmospheric type system the steam temperature is normally:
a) 121˚C b) above 121˚C c) 105˚C d) below 105˚C e) below 50˚C |
d) below 105˚C
note: In the sub-atmospheric system, steam temperatures can be varied from 55˚C (under a high vacuum condition) to 105˚C (under a no vacuum condition).
Pressure and temperature vary depending on weather conditions. |
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In all steam heating systems the horizontal steam supply pipes between boiler and heating units are called the:
a) risers b) mains c) branches d) return lines e) distributing lines |
b) mains |
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In the one-pipe system, all piping is sloped downward so that the condensate can flow freely by gravity back to the boiler without:
a) causing any flow resistance b) interfering with the flow of the steam c) causing any corrosion d) turning into steam e) without giving giving up its latent heat |
b) interfering with the flow of the steam |
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Excessive makeup water to the condensate return tank can be caused by:
a) manual makeup valve closed b) too low a firing rate c) automatic makeup valve sticking open d) the feedwater being too cold e) oversized piping |
c) automatic makeup valve sticking open |
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The arrangement of the piping and heating units of a steam heating system should allow:
a) the condensate to be removed freely from the heating units b) the air to be kept at the top of the heating units c) steam to flow freely to all heating units d) the minas and return mains to be located beside each other e) the mains and return mains to be located at a distance from each other |
c) steam to flow freely to all heating units |
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Another name for the "one pipe" steam heating system is:
a) vacuum system b) pressure system c) air vent system d) divided-pipe system e) vapor system |
c) air vent system |
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Slow or insufficient heat throughout a building heated by steam can be caused by:
a) too high a firing rate b) too low a firing rate c) air leaks d) the feedwater being too cold e) oversized piping |
b) too low a firing rate |
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Slow or insufficient heat in one or more rooms in a steam heated building can be caused by a:
a) faulty steam trap b) faulty float switch c) faulty heater d) faulty vacuum switch e) faulty sight glass |
a) faulty steam trap |
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Finned convectors should be kept free of:
a) air current b) steam c) corrosion d) dust e) water |
d) dust |
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In the variable vacuum system, the vacuum in the condensate return system is maintained __________ the vacuum in the supply main.
a) lower than b) 7 to 10 kPa lower than c) 58 to 61 kPa lower than d) the same as e) higher than |
e) higher than |
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Which of the following would you expect to find in a steam heating system? (choose all that apply)
[a] convectors [b] return traps [c] condensate tank [d] cushion tank |
[a] convectors [b] return traps [c] condensate tank |
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In the case of radiators and convectors, the main sources of trouble are the:
a) air vents b) air traps c) push nipples d) connecting rods e) valves and traps |
e) valves and traps |
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For domestic applications, the temperature of the water in the forced circulation hot water heating system may be as high as:
a) 150˚C b) 121˚C c) 102˚C d) 77˚C e) 50˚C |
c) 102˚C |
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Which of the following use a boiler in the system? (Choose all that apply)
[a] steam heating [b] electric heating [c] steam to hot water system [d] hot water heating |
[a] steam heating [c] steam to hot water system [d] hot water heating |
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A forced hot water circulating system can be classified as which of the following types?
[a] series loop system [b] one pipe system [c] two pipe direct return system [d] two pipe reverse return system [e] three pipe forced |
[a] series loop system [b] one pipe system [c] two pipe direct return system [d] two pipe reverse return system
note: "Multi-zone system" is another type |
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A hot water boiler of the same output is:
a) larger than a steam boiler b) smaller than a steam boiler c) the same size as a steam boiler d) taller than a steam boiler e) shorter than a steam boiler |
b) smaller than a steam boiler |
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In a one pipe hot water system, what is the fitting called that directs the water to each converter?
a) diverter b) trap c) vent valve d) separator e) lead |
a) diverter |
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Snow melting systems are usually filled with:
a) water only b) methanol and water c) ethylene glycol and water d) steam e) warm air |
c) ethylene glycol and water |
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What is the maximum temperature of water in a gravity hot water system?
a) 65˚C b) 70˚C c) 77˚C d) 87˚C e) 67˚C |
c) 77˚C |
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Advantages of the gravity systems are:
a) large pipe sizes b) good circulation especially if heating units are on the same level as the boiler c) quick response to changes in heat demand d) simple operation and low maintenance e) higher heating capacity |
d) simple operation and low maintenance |
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What is the maximum SURFACE temperature of the floor in a radiant heating system?
a) 10˚C b) 20˚C c) 30˚C d) 40˚C e) 50˚C |
c) 30˚C
note: maximum SURFACE temperature for walls is 38˚C and for ceilings is 46˚C in radiant panel heating systems |
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Automatic snow melting systems can use: (Choose all that apply)
[a] a hot water and antifreeze mixture [b] electric resistance heating [c] infrared lamps mounted above sidewalks and ramps [d] a hot water and ethylene glycol mixture [e] hot water and light oil mixture |
[a] a hot water and antifreeze mixture [b] electric resistance heating [c] infrared lamps mounted above sidewalks and ramps [d] a hot water and ethylene glycol mixture |
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The temperature of the WATER in the radiant panel heating should not be higher than _______ for floors.
a) 100˚C b) 90˚C c) 80˚C d) 70˚C e) 60˚C |
e) 60˚C
note: The temperature of the WATER should not be higher than 80˚C for ceilings in the radiant panel heating system. |
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In a hot water system compared to a steam heating system, if there is a leak damage will:
a) be greater in the steam system b) be greater in the hot water system c) be about the same in either system d) depend on where the boiler is located in the system e) be minimal due to the automatic drain system |
b) be greater in the hot water system |
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What is a hot water system which circulates water through the pipes by natural convection known as?
a) a circulating system b) a forced system c) a pumped system d) a gravity system e) a return system |
d) a gravity system |
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Which of the following is not true for the forced circulation systems?
a) smaller pipe sizes b) positive circulation c) fast response to changes in heat demand d) low maintenance e) increased power costs |
d) low maintenance |
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A hot water system which circulates water through the pipes with a pump is known as a:
a) circulating system b) forced system c) pumped system d) gravity system e) return system |
b) forced system |
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In the loop system, the water passes through the entire loop getting progressively:
a) slower b) faster c) hotter d) cooler e) lighter |
d) cooler |
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In radiant heating system changes are:
a) difficult to make b) easy to make c) as easy to make as in any other heating system d) dependent on availability of materials e) dependent on location |
a) difficult to make |
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The temperature control on a steam to hot water converter controls:
a) the pump speed b) the steam temperature c) the water flow d) the steam control valve e) the firing rate |
d) the steam control valve |
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To avoid cavitation in the pump and drawing of air into the system, the pressure at the highest point of the system should be at least:
a) 103 kPa b) 69 kPa c) 12 kPa d) 1.2 kPa e) 1.0 kPa |
c) 12 kPa |
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Welding slag in new hot water heating systems may: (Choose all that apply)
[a] hinder circulation [b] lower the pH of the water [c] burn out motors [d] cause excessive noise |
[a] hinder circulation [c] burn out motors [d] cause excessive noise |
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An in-line circulator is a:
a) reciprocating pump b) gear type pump c) low head pump d) high head pump e) regenerative pump |
c) low head pump |
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Heating system noises can be caused by:
a) closed valves in the system b) air pockets c) pump cavitation d) water temperature too low e) restricted ventilator air flow |
c) pump cavitation |
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If the discharge pressure of the pump is 124 kPa and the pressure differential developed by the pump is 207 kPa, what will be the pressure on the suction side?
a) 124 kPa b) 207 kPa c) 331 kPa d) 83 kPa e) -83 kPa |
e) -83 kPa
note: Suction side pressure = Discharge pressure - Pressure developed by the pump
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Causes of insufficient circulation can be attributed to: (Choose all that apply)
[a] circulator not operating [b] clogging of connections and valves [c] plugging of screen in pump suction [d] high net positive suction head |
[a] circulator not operating [b] clogging of connections and valves [c] plugging of screen in pump suction |
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When the hygroscopic discs used in an automatic vent are in contact with water, they will:
a) contract b) swell c) change in color d) decompose e) open the vent port |
b) swell |
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The presence of air in a hot water heating system will cause: (Choose all that apply)
[a] reduced water flow [b] insufficient heating [c] noisy operation [d] corrosion [e] tube filming |
[a] reduced water flow [b] insufficient heating [c] noisy operation [d] corrosion |
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What type of boiler would you expect to find in a hot water system, incorporating a converter?
a) hot water boiler b) steam boiler c) forced circulation boiler d) reverse flow boiler e) once through boiler |
b) steam boiler |
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Improper location of the circulating pump and expansion tank can cause: (Choose all that apply)
[a] the circulating pump to cavitate [b] some points in the system to be under negative pressure [c] air to be drawn into the system [d] vapour bubbles to form in the circulating pump [e] low pressure steam to accumulate in the piping |
[a] the circulating pump to cavitate [b] some points in the system to be under negative pressure [c] air to be drawn into the system [d] vapour bubbles to form in the circulating pump |
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Hygroscopic means:
a) readily absorbs water b) hot water c) readily rejects any water d) an instrument which measures humidity e) an instrument which measures water flow rate |
a) readily absorbs water |
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To regulate the flow of water to a zone circuit a:
a) flow control valve is used b) diverter fitting is used c) gate valve is used d) pressure reducing valve is used e) balancing valve is used |
e) balancing valve is used |
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The expansion tank is normally attached to the:
a) boiler or the hot water supply line near the boiler b) highest point in the system directly above the boiler c) supply line after the circulating pump d) supply line above the lowest convector e) return line directly before the boiler |
a) boiler or the hot water supply line near the boiler |
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A flow control valve is a:
a) lift type check valve b) modulating control valve c) needle valve d) relief valve e) one way check valve |
a) lift type check valve |
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To prevent corrosion in the expansion tank it is sometimes filled with:
a) nitrogen b) air c) oxygen d) helium e) hydrogen |
a) nitrogen |
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Excessive pressure build-up due to a rise in temperature and the resulting expansion of the water in the system is prevented by the use of:
a) a float tank b) a relief valve c) an expansion tank d) a cushion valve e) a safety valve |
c) an expansion tank |
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Insufficient heat throughout a building heated by hot water can be caused by:
a) too high a firing rate b) main supply head temperature being too high c) boiler water temperature being too low d) the feedwater being too hot e) oversized piping |
c) boiler water temperature being too low |
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206 kPa is equivalent to a head of water of:
a) 0.5 m b) 1.0 m c) 15 m d) 21 m e) 25 m |
d) 21 m
note: divide the pressure by 9.81 to get this answer |
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Insufficient heat in one or more rooms in a hot water heated building can be caused by:
a) faulty steam traps b) air pockets in heating units c) too high a firing rate d) faulty vacuum switches e) oversized heating units |
b) air pockets in heating units |
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Valves in heating systems should be ____________ if they do not shut off tightly.
a) discarded b) heated c) bypassed d) repaired e) reported |
d) repaired |
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if the suction pressure of the pump is 124 kPa and the pressure differential developed by the pump is 55 kPa, what will be the pressure on the discharge side?
a) 124 kPa b) 55 kPa c) 69 kPa d) 179 kPa e) 103 kPa |
d) 179 kPa
note: Discharge pressure = Suction side pressure + Pressure developed by the pump |
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The advantage of having duct furnaces instead of a large central furnace is
a. less initial cost |
c. better control of heat in each zone of the building |
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Which of the following is not an advantage of a forced air heating system?
a. air may be cleaned by filters b. air can be humidified by using a humidifier c. positive air circulation promotes a more uniform temperature distribution d. the ducts are much smaller than a gravity system e. blower noise can be carried through the ducts |
e. blower noise can be carried through the ducts |
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The vent damper minimized heat loss up the stack:
a. when burners are on b. when burners are off c. by shutting off burners d. by reducing firing rate e. by increasing combustion air flow |
b. when burners are off |
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In a fin-coil heat exchanger the primary source of heat for the exchanger is
a) steam or hot water |
a) steam or hot water |
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The power supply for an electric resistance coil furnace is
a) 60 V |
c) 240 V |
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A type of directly fired space heater is
a) a unit heater |
d) all of the above |
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Furnace efficiency can be improved by:
1. installing of a vent damper 2. using electronic ignition 3. improving heat exchanger design 4. adding a secondary heat exchanger 5. removing a secondary heat exchanger
a. 1,2,3 b. 2,3,4,5 c. 1,2,3,4 d. 3,4 e. 1,3,5
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c. 1,2,3,4 |
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Which three items give the forced warm air system a definite advantage over steam and hot water heating systems?
1. the ducts are much smaller 2. air can be cleaned by filters 3. air can be humidified using a humidifier 4. controlled quantities of external ventilation air may be drawn into the system 5. blower noise can be carried through the ducts
a. 1,2,3 b. 2,3,5 c. 2,3,4 d. 3,4,5 e. 1,2,4 |
c. 2,3,4 |
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Lowboy furnaces are just over
a) 1.0 m in height |
e) 1.2 m in height |
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In a warm air heating system the cold air return registers are located
a) in exterior walls |
b) in interior locations |
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The downflow furnace has the blower located ______ the heat exchanger discharging _________.
a. above, upward b. above, downward c. below, upward d. below, downward e. below, horizontally |
b. above, downward |
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Before vent dampers and electric ignition were developed, what type of efficiencies did warm air furnaces typically develop?
a. 94 - 98% b. 80 - 95% c. 70 - 75% d. 60 - 80% e. 40 - 50% |
c. 70 - 75% |
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In a warm air heating system, the blower forces the air through the heat exchanger, where it is:
a. cooled b. warmed c. purified d. filtered e. mixed with outside air |
b. warmed |
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Which of the following are types of heat sources used in warm air heating systems?
1. fin-coil heat exchanger 2. directly-fired 3. electric resistance coil 4. glycol heater 5. heavy oil heating
a. 1,2 b. 1,2,3 c. 2,3,4 d. 1,2,3,4 e. 3,4,5 |
b. 1,2,3 |
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In a pulse combination furnace the stated efficiency is:
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a) 94 - 98% |
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Forced warm air furnaces are classified by direction of air flow as:
[a] horizontal [b] lowboy [c] upflow [d] downflow
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[a] horizontal [c] upflow [d] downflow |
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The airborne contaminants are removed from the plates of electronic filters by:
a. blast of high pressure air b. reversal of the air flow direction through the filter c. washing d. periodic replacement of the plates e. using a rapper system to knock the particles loose
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c. washing |
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Air ducts are made of materials such as:
1. corrugated plastic 2. aluminum 3. fiberglass 4. galvanized sheet metal
a. 1,2,3 b. 2,3 c. 1,4 d. 2,3,4 e. 2,4
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d. 2,3,4 |
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In a warm air heating system, the heated air should enter the rooms preferably via the
a) high wall registers on the inside wall |
c) baseboard registers on the outside wall |
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The HEPA filters require:
a. at least one or two stages of pre-filtering b. at least one or two stages of after-filtering c. washing every six months d. replacement every six months e. a few drops of oil every six months |
a. at least one or two stages of pre-filtering |
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Rooms that are stuffy and dry are created by
a) poor air distribution |
e) the humidifier not working |
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The perimeter loop system of furnace ducting is ideal for a building with
a) no insulation in the walls |
c) no basement |
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Sleeve bearings on furnace fans require
a) no lubrication |
c) a few drops of oil every six months |
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Which of the following is not a type of outlet in a warm air heating system?
a. a grill b. a register c. a ceiling diffuser d. a perforated panel e. a plenum |
e. a plenum |
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When perimeter loop or radial systems are used in a building without a basement, the furnace used should be of the _______ type.
a. horizontal b. upflow c. downflow d. gas-fired e. oil-fired |
c. downflow |
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Which of the following is a type of outlet in a warm air heating system?
a) a grill |
e) all of the above |
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Electronic filters will remove
a) all particles from the air |
b) fine particles from the air |
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Insufficient heat throughout a building is likely caused by
a) too high an air flow |
b) insufficient heat input |
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Dry and viscous filters will remove:
a. all particles from the air b. fumes from the air c. odour producing gases from the air d. smoke from the air e. coarse particles of dust from the air |
e. coarse particles of dust from the air |
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Which of the following is not a furnace component?
a. heat exchanger b. combustion equipment c. blower d. motor e. grill |
e. grill |
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Heat exchangers in gas fired furnaces are made of:
a. brass b. copper c. aluminum d. steel e. cast iron |
d. steel |
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The plenum temp in a warm air heating system should be at least what temp?
a. 100 b. 80 c. 70 d. 65 e.38 |
d. 65 |
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Plugged _______ on warm air heating and ventilating systems limit the air flow and result in insufficient heating and a waste of fuel.
a. filters b. drain lines c. diverters d. univents e. convectors |
a. filters |
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In warm air heating systems, what are normally installed in all the branch ducts near their takeoff point on the plenum?
a. dampers b. registers c. grilles d. diffusers e. perforated panels |
a. dampers |
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Electronic air filter use an arrangement of wires charged with ___________ volts DC.
a. 5000 b. 8000 c. 9000 d. 10 000 e. 13 000 |
e. 13 000 |
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1 micron is:
a. 1 mm b. 10mm c. one-thousandth of a mm d. one-thousandth of a m e. 1m |
c. one-thousandth of a mm |
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Electrostatic filters are highly efficient in the removal of:
a. dust and pollen b. fine dust, smoke and fumes c. bacteria and spores d. lint e. mists and fog |
b. fine dust, smoke and fumes |
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The air velocity through a viscous filter can be _____ times higher than with dry filters.
a. 10 b. 6 c. 5 d. 3 e. 2 |
a. 10 |
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Which of the following is a vapour form of contaminant in the air?
a. fine dust b. lint c. bacteria d. pollen e. odour |
e. odour |
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Ventilation can be divided into two basic methods:
a) forced and natural |
b) mechanical and natural |
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The recommended minimum ventilation rate for most occupied areas is about ____ air change(s) per hour.
a. 5 b. 4 c. 3 d. 2 e. 1 |
e. 1 |
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Dry filters are highly efficient in the removal of:
a. fine dusts, fumes and smoke b. bacteria and spores c. lint d. corrosive gases e. mists and fog |
c. lint |
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Activated alumina chemisorbant media is used to remove _________ from the air.
a. dust and pollen b. insects c. corrosive gas d. dirt e. lint |
c. corrosive gas |
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The advantages of the common exhaust duct system are its:
[a] simple design [b] relatively low cost [c] ease of maintenance [d] fume disposal away from windows, air intakes, etc. [e] efficiency dealing with pollen
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[a] simple design [b] relatively low cost [c] ease of maintenance [d] fume disposal away from windows, air intakes, etc. |
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Living organisms that must be removed from the air are
a) insects and pollen |
c) bacteria and spores |
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Viscous filters are highly efficient in the removal of
a) fine dust, fumes, and smoke |
d) dust and pollen |
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Which of the following is a liquid form of contaminant in the air?
a. dust b. insects c. mists d. fume e. lints |
c. mists |
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Actual ventilation rates may vary per person from
a) 0.5 to 0.6 cubic metres/min |
d) 0.14 to 1.5 cubic metres/min |
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Another name for a rotating type air filter is:
a. dry filter b. viscous filter c. curtain filter d. electronic filter e. charged-media filter |
c. curtain filter |
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Mechanical filters can be divided into two broad classes:
a) wet and dry |
e) throwaway and renewable |
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Natural ventilation is improved by the use of a roof
a) ventilator |
a) ventilator |
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Activated alumina chemisorbant is impregnated with:
a. a reducing agent b. an oxidizing agent c. oil d. water e. none of listed items |
b. an oxidizing agent |
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The air velocity through a dry filter is usually no more than:
a. 1.25 m/s b. 0.75 m/s c. 0.50 m/s d. 0.25 m/s e. 0.20 m/s |
d. 0.25 m/s |
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The activated carbon in an odour absorber may be reactivated by heating it to ______ ˚C to drive out the absorbed gases.
a. 325 b. 230 c. 500 d. 538 e. 121 |
d. 538 |
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The activated carbon can absorb odour-causing gases from the air up to about ______ of its own weight.
a. 10% b. 15% c. 20% d. 40% e. 60% |
c. 20% |
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The germicidal lamp emit ______ which effectively destroys bacteria and spores in the air.
a. sun light b. infrared light c. ultraviolet light d. CI2 e. superheated steam |
c. ultraviolet light |
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Unvented surface combustion heaters require sufficient ventilation be provided to remove combustion gases and to prevent:
a. overheating b. excessive moisture buildup c. cold draft d. pressure buildup e. none of the listed items |
b. excessive moisture buildup |
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A low temperature catalytic heater contains a layer of
a) metal impregnated with a catalyst |
d) glass wool impregnated with a catalyst |
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Infrared heaters send out radiant energy in the form of:
a. visible infrared waves b. invisible infrared waves c. ultraviolet light d. electric current e. air current |
b. invisible infrared waves |
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In a surface combustion heater, the gas and combustion air are mixed in the upper chamber at a pressure:
a. well below atmospheric b. slightly below atmospheric c. slightly above atmospheric d. well above atmospheric e. none of the listed items
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c. slightly above atmospheric |
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The emitting surface temperature of a quartz lamp is about:
a. 845˚C b. 930˚C c. 1260˚C d. 1700˚C e. 2200˚C |
e. 2200˚C
note: The emitting surface temperature of a, Metal Sheath = 845˚C Quartz Tube = 815-930˚C Quartz Lamp = 2200˚C |
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The basic types of heating systems are:
a) 1, 2, 4 |
d) 1, 2, 3, 4 |
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Electric heating can be divided into two general groups:
a. floor and wall b. direct and indirect c. wall and baseboard d. radiant panel and infrared e. direct and infrared |
b. direct and indirect |
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In an internally fired, gas fired infrared heater, the surface temperature is about
a) 300 degrees C |
b) 400 degrees C |
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Electric heating elements are made of metals which:
a. burn to produce radiant heat b. offer low resistance to the flow of electric current c. offer high resistance to the flow of an electric current d. offer no resistance to the flow of an electric current e. react with air to produce radiant heat |
c. offer high resistance to the flow of an electric current |
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Gas-fired infrared heaters use the principle of
a) heating a gas |
b) heating a solid surface |
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In an open wire type heating element the resistance wire is made of
a) tungsten |
e) nickel-chromium |
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Infrared radiant energy is directed towards
a) ceilings |
d) floors |
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The radiating surface of a directly-fired refractory heater is heated by:
a. slow oxidization reaction b. nichrome element c. burner flame d. combustion gases e. warm air |
c. burner flame |
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In an electric snow melting unit, a thermostat should be used to automatically shut the system down when the outdoor temperature is above
a) 0 degrees C |
c) 2 degrees C |
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Infrared heaters are usually mounted
a) overhead |
a) overhead |
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Spot heating covers only a very small area and is used on:
1. loading docks 2. opening work sheds 3. bus stop shelters 4. warehouse heating 5. domestic central heating system
a. 1,2 b. 1,2,3 c. 2,3,4 d. 3,4,5 e. 1,3,5 |
b. 1,2,3 |
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The main disadvantage of electric heating is the
a) high maintenance cost |
d) high operating cost |
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Infrared heaters heat the solid, opaque object by:
a. conduction b. convection c. radiation d. hot flue gases e. warm air |
c. radiation |
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Blowers used in warm air furnaces are usually of __________ type:
a) reciprocating b) gear c) rotary d) centrifugal e) regenerative |
d) centrifugal |
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The extended plenum system cannot be installed in:
a) the basement b) false ceiling c) a crawl space d) an attic e) a concret slab floor |
e) a concret slab floor |
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Which type is a mechanical ventilation system?
a) natural air intake, natural exhaust b) mechanical air intake, natural exhaust c) natural air intake, no exhaust d) natural intake, natural exhaust e) none of the listed options |
b) mechanical air intake, natural exhaust |
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The quartz lamp heating element will respond:
a) instantaneously b) in a few seconds c) in about one minute d) in about thirty seconds e) in about three minutes |
b) in a few seconds
note: These heating elements will respond in: Metal sheath = 3 minutes Quartz tube = 1 minute Quartz lamp = a few seconds |
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Hand operated pet cocks on heating systems used for expelling air have been superseded by:
a. steam traps b. diverters c. automatic air vents d. check valves e. pipe siphons |
c. automatic air vents |
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Radiators can be classified as
a) floor, window, or ceiling |
c) wall-hung, floor, legless, and window |
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A pressure balancing device that prevents the boiler pressure from forcing the water in the boiler into the return line is called a:
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e. Hartford loop |
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In the variable vacuum system, the rate of steam supply can be adjusted by:
a. gate valve b. automatic modulating control valve c. steam trap d. check valve e. air vent |
b. automatic modulating control valve |
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Steam converters are used in hot water heating systems to:
a. transfer the heat contained in the steam to the water b. change the direction in which the water is flowing as it cools down c. change condensate back to steam d. reduce the pressure in the expansion tank e. to replace the steam boiler |
a. transfer the heat contained in the steam to the water |
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The purpose of an expansion tank is to:
a. store heat while the boiler is firing b. allow for the expansion of water in the system c. prevent the system from overflowing d. prevent the water in the system from freezing e. prevent water lock in the system |
b. allow for the expansion of water in the system |
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The minimum reading on an altitude gage of a boiler in a large plant is from the top of the boiler to the highest point in the system plus
a) 0.6 m |
d) 1.2 m |
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Which of the following would you do first to fill up and start up a hot water heating boiler and system?
a. admit water to the system b. switch on the power supply to the boiler c. switch on the power supply to the pump d. open all vents and close all drains e. shut off the burner |
d. open all vents and close all drains |
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Which of the following would you expect to find in a steam heating system?
[a] convectors [b] expansion tank [c] circulating pump [d] automatic fill valve |
[a] convectors [b] expansion tank [c] circulating pump [d] automatic fill valve |
