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19 Cards in this Set
- Front
- Back
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Fuel should be shut off immediately if it fails to ignitea) to save fuelb) to prevent furnace explosionsc) to prevent spillsd) to save powere) to prevent boiler corrosion |
b) to prevent furnace explosions |
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A thermocouplea) consists of two similar wiresb) produces an electric signalc) senses infrared light from the flamed) senses changes in fuel line pressuree) senses changes in air pressure |
b) produces an electric signal |
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Thermocouples are connected in series toa) monitor more than one flame sourceb) increase the sensitivity of the detection systemc) generate a higher voltaged) provide a spare thermocouple in case of failure of onee) none of the above |
c) generate higher voltage |
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A flame roda) forms an electric circuit with the rod, flame and relayb) is used for gas and oil fired burnersc) forms an electric circuit with the rod, flame and burnerd) senses the temperature of the flamee) is used to light the main burner |
c) forms an electric circuit within the rod, flame and burner |
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A flame scanner(1) requires a photoelectric cell(2) responds to temperature changes(3) requires a clear line of sight to the flame(4) produces a steady voltage signala) all of the above are correctb) 1 & 2 are correctc) 1, 2, & 4 are correctd) 1 & 3 are correcte) none of the above |
d) 1 & 3 are correct |
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The function of a flame failure device is toa) shut off the fuel supply when the pressure gets too highb) shut off the fuel when the burner flame goes outc) shut off the fuel when the fuel temperature is highd) shut off the feedwater supply to the boilere) de-energize the fan and feedwater systems |
b) shut off the fuel when the burner flame goes out |
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Which of the following is a flame sensing device?a) thermopileb) heat sensing controlc) stack relayd) cut-off valvee) scanner |
e) scanner |
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A flame failure devicea) must be installed on every high pressure boilerb) will shut off the steam leaving the boilerc) will control the pressure of the boilerd) will shut off the fuel to the burnere) will shut down the flame in the boiler |
d) will shut off fuel to the burner |
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The maximum allowable temperature for the water in a hotwater heating boiler isa) 100 degrees Cb) 150 degrees Cc) 120 degrees Cd) 170 degrees Ce) 250 degrees C |
c) 120 degrees C |
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High limit temperature controlsa) increase air flow to the boiler if temperature limits areexceededb) open a 3-way mixing valve to add cold water to the hotwater to reduce the water temperaturec) are required on steam boilersd) are required under Section II of the ASME Codese) shut off the fuel if the water temperature is too high |
e) to shut off the fuel if the water temperature is too high |
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Flame rodsa) should be cleaned of deposits regularlyb) should not be exposed to temperatures above 100 degrees Cc) should shut off the fuel within four seconds of flamefailured) are very reliable and maintenance freee) require frequent filing of electrical contacts to preventcorrosion build-up and failure of the device |
c) should shut off the fuel within four seconds of flame failure |
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All flame safeguard devicesa) activate an alarm system if flame failure is detectedb) require a photoelectric cellc) are limited to temperatures comfortable to the handd) monitor the pilot flame and main burner simultaneouslye) close the main fuel valve in case of pilot flame failureor main burner failure |
e) close the main fuel valve in case of pilot flame failure or main burner failure |
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Flame safeguard devicesa) are all unaffected by heatb) should be kept as far away from the fire as possiblec) should not be cleaned except by a qualified servicemand) should be kept cool enough to be touched by hande) should be tested following the manufacturers instructions |
e)should be tested following the manufacturers instructions |
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If a high temperature limit is detected by the limit controller it will shut off the gas supply the pilot flame.
a) true b) false |
a) True |
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If no high temperature exists to trip the limit controller, the thermostat switch closes when low air temperature occurs. This thermostat then: a) opens the main gas valve b) ignites the pilot burner c) opens the gas pressure reducing valve d) energizes the pilot stat |
a) opens the main gas valve |
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The outer sheath of a thermocouple used with a pilot burner is made of: a) copper b) nickel c) aluminum d) molybdenum |
a) copper |
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a Photocell flame detection device is often called a: a) thermocouple b) scanner c) flame rod d) thermister |
b) scanner |
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The maximum temperature for a lead sulphide scanner is: a) 35 degrees C b) 65 degrees C c) 75 degrees C d) 50 degrees C |
d) 50 degrees C |
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The ultraviolet scanner is mounted as close to the flame as physically possible without subjecting it to a temperature over ______ a) 50 degrees C b) 100 degrees C c) 75 degrees C d) 95 degrees C |
b) 100 degrees C |
