hvacr gas heating esco Questions and Correct Answers/ Latest Update / Already Graded

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hvacr gas heating esco Questions and
Correct Answers/ Latest Update /
Already Graded
using an ohmmeter, there is 120 VAC between high speed and

ground wires, this indicates


Ans: open




if temperature rise is too high...


Ans: increase fan speed




how many of the 3 OSHA conditions defining confined spaces must

be met


Ans: all 3




what causes the temperature limit safety switch to shut off the burner


Ans: fan motor failure

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flashback indicates


Ans: the gas is flowing slower than the speed at which burn is occurring




what type of connector is used to control noise in ductwork


Ans: vibration eliminators




if the main burner lights and after a minute the blower fan comes on

but the burner flames waver in one corner...


Ans: there is faulty blower housing




a burner orifice...


Ans: meters gas to the burner




when lockout/tagout is used


Ans: there should be 1 key kept by the electrician

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the gas pressure is usually


Ans: 3.5




a spark igniter operates at


Ans: 7,500 vac




a good thermocouple produces


Ans: 30 millivolts




what must be present for combustion


Ans: air, fuel and ignition source




the innerds of a type b vent is made of


Ans: aluminium




the outsides of a type b vent is made of