ESCO Electric Heat - HVAC Excellence Exam (Answered)

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ESCO Electric Heat - HVAC Excellence Exam (Answered) Before working on an electric furnace the tech should All the above: Review diagram, remove jewelry, and follow safety procedures. A GFCI circui... t breaker detects current leaks to ground The conductor in an electric heat element is usually made of Nichrome An example of resistive load is crankcase heater An example of an inductive load is Motor An electric furnace is marked 208/230 single phase 60Hz A tech reads 200 vac at the power supply and determines the voltage is too low Voltage imbalance between any legs of 3 phase power supply may not exceed 2% The limit switch on an electric furnace is a Automatic reset switch The sequencer timers on electric heater will usually energize the 1st heating element after a time delay of 1 to 30 sec The amount of btus produced by 1 watt of electricity is 3.413 btus A tech reads 60 amps with a clamp on amp meter on a forced air furnace. The supply voltage is 230 volts AC, approx how many watts is the furnace using 13,800 A furnace is using 15,500 watts approx Kw 15.5 Kw A sequencer timer use _____ to close the contact points to the heater element heated snap-discs or bi-metal strips An electric furnace heating thermostat must open on rise close on drop A standard thermostat heat anticipator is ____ and wired in ____ with the heating control adjustable/series Some thermostat manufacturers require a jumper connection on the thermostat subbase of heating and cooling thermostat in order to use a single transformer Most electric heat elements use the following safties to prevent overheating snap disc and fusible link A tech reads 70 amps to the single phase heater. The supply voltage is 230 volts Ac. Approx how many btus is the furnace producing 54,949 The control that prevents duct heater from operating unless there is adequate supply air is fan interlock The COP for electric resistance heat is 1 to 1 What is the maximum kW element used on each contact of a residential heat sequencer 5 Kw Electric heaters are generally rated at ____ volts ac for kW output 240 The first stage of a sequencer usually has a set of contacts to start the blower fan motor An automatic reset safety on a heater element generally opens at ____*F 130-190*F Most heating elements are mounted on which type of insulator mica or ceramic A 10 kW electric heater operating at 240 v draws 42 amps, what will a 10 kW heater wired to 480 volts draw 21 amps The purpose of a sequencer is to avoid a sudden power load [Show More]

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