Exam 43: Air Source Heat Pumps

The coil that serves the inside of the house in a heat pump is known as the ____________________.

What is the formula for the COP of a heat pump operating in the heating mode?

The main valve in a pilot-operated four-way reversing valve is moved by pressure created by the ____.

A common metering device is a combination flow device and check valve. This device is referred to as a(n) ____________________.

When brazing a four-way reversing valve, a wet rag could be wrapped around the body of the valve to minimize the chance of internal damage to the valve.

The coefficient of performance of a heat pump operating in the heat mode tends to ____________________ as the outside air temperature drops.

The water-to-air heat pump might not need auxiliary heat because the water can be at relatively constant temperature all winter.

Termination of the defrost cycle by temperature occurs when the temperature sensor reaches ____.

A common method of starting defrost uses an air pressure switch that measures the difference in pressure ____.

What action must the four-way reversing valve take to operate the heat pump system in the defrost mode?

In time-temperature defrost controls, the temperature that actuates the control is the temperature of the ____________________ coil.

TXVs used in cooling-only air-conditioning units and heat pumps are interchangeable as long as they are the same size and for the same refrigerant.

____________________ involves the removal of heat from a place where it is not wanted and depositing it in a place where it makes little or no difference.

Why must the air from a heat pump operating in the heating mode be distributed carefully?

During operation, the compressor motor will rotate in the opposite direction to change the direction of refrigerant flow.