40 ch
____ controls are needed to monitor ice buildup on the outdoor coil of an air-to-air system.
Defrost
Which of the following statements about charge compensator tanks is false?
During the cooling mode, the gas line cools liquid refrigerant in the tank.
Basic heat pump theory rests on the principle that heat moves naturally from cooler substances to warmer substances.
False
Which of the following statements about a heat pump operating in cooling mode is false?
The compressor pumps high-pressure refrigerant vapor into the indoor coil.
Which of the following statements about flow check pistons is false?
They meter refrigerant passing through in either direction.
An air-source heat pump's heating cycle ____ as the outdoor temperature drops.
becomes less efficient
A ground-source heat pump that circulates refrigerant through an outdoor coil that is placed in direct contact with the earth is a(n) ____ heat pump.
direct-exchange
When a heat pump is operating in heating mode, the outdoor coil functions as a(n) ____ by absorbing heat.
evaporator
During winter heating, a heat pump system only requires temperature controls to keep the system operating.
false
Heat pump systems can use just two standard TXVs piped in series to regulate refrigerant flow for normal operation in heating or cooling mode.
false
Solar heating systems help heat pumps provide heating at a significant operating cost.
false
The direction of refrigerant flow through a compressor in a heat pump system changes direction when the system switches between heating and cooling modes.
false
The smaller line in a heat pump system is referred to as the suction line.
false
A heat pump that uses the earth as a heat source or a heat sink for producing the desired temperature in a conditioned space is a(n) ____ heat pump.
ground-source
Auxiliary heat for a heat pump ____.
may use electric heating coils in the supply air ducts Correct! All of the above. is not as efficient as normal system operation is needed when it is not possible for the heat pump to extract enough heat from the outside air
A heat pump with a 13-SEER rating is ____ a 12-SEER heat pump.
more efficient than
A reversing valve that uses a solenoid valve to direct high- and low-pressure refrigerant to move the sliding section within the valve body is a ____.
pilot-operated reversing valve
To prevent snow from blocking side airways, install ____.
risers
A crankcase heater warms a heat pump compressor to vaporize any liquid refrigerant that may have entered the compressor during the Off cycle
true
A ground coil is an underground length of tubing through which refrigerant is circulated.
true
A water loop circulates water through a length of tubing that is submerged in a body of water.
true
During the cooling mode in a heat pump, the reversing valve routes refrigerant from the compressor to the outdoor coil.
true
In a solar heating system, a hydronic coil is placed in the air handler plenum.
true
Suction line accumulators are used in heat pump systems to protect the compressor from liquid slugging.
true
A heat pump that circulates water through a secondary circuit that is placed underground or underwater is a(n) ____ heat pump.
water-source
Which of the following statements about heat pump compressors is false?
One-way filter-driers protect the compressor from liquid slugging.
Solar panels used in conjunction with heat pump systems ____.
absorb heat from the sun
A heat pump that uses the outside air as a heat source or a heat sink for producing the desired temperature in a conditioned space is a(n) ____ heat pump.
air-source
Nearly ____% of all energy used in the home is for heating and cooling.
50
How should you clean the outdoor unit of a residential heat pump?
Apply a non-acid coil cleaner and rinse with water.
