NATE Heat Pump Exam Best Answers 2024-2025
A disc-type, close-on -rise pressure control is being used as a loss-of-charge limit control on the liquid
line of a heat pump. The control must sense a specified pressure within __ _______ of a compressor
start for the compressor to continue operation. If the cut-in setting of the control drifts lower, the
system is less likely to shut down as a result of a small leak - ANSWER-15 seconds
The sensor of an outdoor ambient thermostat for a heat pump system is typically installed in the -
ANSWER-entering airstream to the outdoor coil
A high pressure limit control, used to shut down a compressor if condensing pressure becomes
excessive, is typically installed to sense - ANSWER-compressor discharge line pressure
Low pressure limit controls are often placed in the suction line of a heat pump for two purposes. They
are to - ANSWER-protect the compressor if suction pressure drops too low and to detect a loss of a
charge
The function of a reversing valve is to provide - ANSWER-heating and/or cooling
The relationship between inrush current and holding current of a relay coil is inrush current is -
ANSWER-always greater than holding current
The capability of electronic programmable room thermostat to reset the set point early so that the
space temperature reaches a set temperature at a specific time is called - ANSWER-computed
recovery
When using a double (dual) element time-delay fuse with a 20 amp motor, the maximum fuse size
should be - ANSWER-25 amps
According to fire protection codes, fire dampers should be used in any air duct that - ANSWER-passes
through all walls or partitions of a light commercial installation
, When the capacity of a heat pump in heating, measured in Btu's, is the same as the heat loss of a
structure, the system is said to have reached its - ANSWER-balance point
A suction line accumulator should be used in a residential heat pump only when - ANSWER-
recommended by the manufacturer if long refrigerant lines increase system charge over recommended
maximum charge
The measurement of a heat pumps efficiency is often stated using its "Coefficient of Performance" or
COP. The COP of a heat pump is the heat pumps - ANSWER-heat output in watts divided by its total
electrical input in watts
The purpose of calculating the heat loss at an outside design temperature is to - ANSWER-select the
appropriate equipment based on Btu output
The minimum circuit amp listed on a units' data plate is used to determine the - ANSWER-max fuse or
circuit breaker size.
Heat pumps are particularly sized based on the - ANSWER-cooling load
The effective method of reducing sound when AHU is located in a closet is to use - ANSWER-vibration
isolators
When wiring a 20 amp FLA motor, the minimum amp fuse or circuit breaker should be - ANSWER-25
The typical staging of a two stage HP system uses the deviation of the t-stat setting to determine -
ANSWER-when to engage each stage.
The purpose of a sequencer in a HP with an AUX 20 kW electric heater is to - ANSWER-energize one or
two elements and the blower then energize the other elements in timed intervals.
A disc-type, close-on -rise pressure control is being used as a loss-of-charge limit control on the liquid
line of a heat pump. The control must sense a specified pressure within __ _______ of a compressor
start for the compressor to continue operation. If the cut-in setting of the control drifts lower, the
system is less likely to shut down as a result of a small leak - ANSWER-15 seconds
The sensor of an outdoor ambient thermostat for a heat pump system is typically installed in the -
ANSWER-entering airstream to the outdoor coil
A high pressure limit control, used to shut down a compressor if condensing pressure becomes
excessive, is typically installed to sense - ANSWER-compressor discharge line pressure
Low pressure limit controls are often placed in the suction line of a heat pump for two purposes. They
are to - ANSWER-protect the compressor if suction pressure drops too low and to detect a loss of a
charge
The function of a reversing valve is to provide - ANSWER-heating and/or cooling
The relationship between inrush current and holding current of a relay coil is inrush current is -
ANSWER-always greater than holding current
The capability of electronic programmable room thermostat to reset the set point early so that the
space temperature reaches a set temperature at a specific time is called - ANSWER-computed
recovery
When using a double (dual) element time-delay fuse with a 20 amp motor, the maximum fuse size
should be - ANSWER-25 amps
According to fire protection codes, fire dampers should be used in any air duct that - ANSWER-passes
through all walls or partitions of a light commercial installation
, When the capacity of a heat pump in heating, measured in Btu's, is the same as the heat loss of a
structure, the system is said to have reached its - ANSWER-balance point
A suction line accumulator should be used in a residential heat pump only when - ANSWER-
recommended by the manufacturer if long refrigerant lines increase system charge over recommended
maximum charge
The measurement of a heat pumps efficiency is often stated using its "Coefficient of Performance" or
COP. The COP of a heat pump is the heat pumps - ANSWER-heat output in watts divided by its total
electrical input in watts
The purpose of calculating the heat loss at an outside design temperature is to - ANSWER-select the
appropriate equipment based on Btu output
The minimum circuit amp listed on a units' data plate is used to determine the - ANSWER-max fuse or
circuit breaker size.
Heat pumps are particularly sized based on the - ANSWER-cooling load
The effective method of reducing sound when AHU is located in a closet is to use - ANSWER-vibration
isolators
When wiring a 20 amp FLA motor, the minimum amp fuse or circuit breaker should be - ANSWER-25
The typical staging of a two stage HP system uses the deviation of the t-stat setting to determine -
ANSWER-when to engage each stage.
The purpose of a sequencer in a HP with an AUX 20 kW electric heater is to - ANSWER-energize one or
two elements and the blower then energize the other elements in timed intervals.
