110 final review 2

What is the condition of a relay coil rated to operate on 24 volts if the coil has a resistance of 50 ohms?

• Good

• Open

• Shorted

• Grounded

If the voltage loss measured across the contacts of a contactor is more than 5% of the line voltage, the contactor __________.

• is good

• should be replaced

• is too large for the application

• Has a faulty coil

What can a technician use to interpret the meaning of the flashing light codes given by the LED on an integrated furnace control board?

• Integrated furnace diagnostic module

• Diagnostic code legend found on the furnace or online from the manufacturer

• Wiring schematic diagram

• All of the choices are correct

Which of the following functions is performed by the defrost control during a defrost cycle on a heat pump?

• De-energize the outdoor fan motor

• Switch the heat pump into the cooling mode of operation by controlling the reversing valve

• Energize the supplementary heating

• All of the choices are correct

What may result if the installation technician does not perform proper and thorough start-up and check procedures on newly installed heating and cooling equipment?

• Shortened equipment life

• Equipment or structural damage

• Inefficient or improper operation

• All of the choices are correct

   

A device used to reverse the flow of refrigerant in a mechanical refrigeration system best describes a ________.

• Thermostatic expansion valve

• Reversing valve

• Check valve

• Solenoid valve

Which of the following choices best represents the common size range, in American Wire Gauge (AWG), of thermostat wire used to make field control wiring connections?

• #12 to #16

• #18 to #20

• #26 to #32

• #4 to #8

When communicating with a customer, it is imperative that the technician listen intently to the customer and treat them as they are ________.

• Important

• Insignificant

• Uninformed

• Incompetent

Which of the following choices represents an advantage of using a compressor with part winding motor starting?

• Higher starting torque

• Lower starting ampacity

• Smaller compressors can be used

• Part winding motors are quieter

What is used to cool water that is supplied to chilled water coils used in commercial systems?

• Water chillers

• Evaporative coolers

• Water coolers

• Direct-expansion cooler