System Hardware
A three-position service valve is distinguished by
no valve core in the port
a square stem extending out
a large top cap
Where are packaged water-source heat pumps normally located?
Inside the building
When is the air coil in a water-source heat pump the acting condenser?
In the heating cycle
A water-source heat pump does not require a defrost cycle because:
The fluid circulating through the water-source unit cannot be allowed to freeze.
A geothermal heat pump system uses the ground as a heat source in heating and a heat sink in cooling. True or False
True
What efficiency advantage do radiant floor systems have over air-source heat pump systems?
Water is a more efficient heat-transfer medium.
When is the water coil in a water-source heat pump the acting evaporator?
In the heating cycle
When is the air coil in a water-source heat pump the acting evaporator?
In the cooling cycle
Why do water-source units not require suction line accumulators or charge compensators?
The water-source unit's capacity is less variable because the water being supplied to it must be moderate in temperature.
A water-source system that recirculates water in pipes buried in the ground is:
A closed-loop system.
The amount of heat that can be carried by water in a small-diameter length of piping will be equal to or greater than the same amount that can be carried with the air in a large duct; which is one advantage of Water-to-air heat pumps.(True or False)
False
Radiant Floor Systems
When is the water coil in a water-source heat pump the acting condenser?
In the cooling cycle
An open-loop system is practical only if:
There is an adequate supply of water and it is of good quality.
What type of defrost do geothermal systems use?
They do not need defrosting.
A closed-loop system is practical only when:
(3 items)
The geology, hydrology, and land availability meet the requirements for system installation.
How can many water-source heat pump systems be configured to supply hot domestic water?
By using de-superheating coils and water-circulating pumps built into many systems
What type of metering device do most packaged water source heat pumps use?
Single bi-flow thermostatic expansion valve
Unlike other types of systems, geothermal systems do not lose capacity as the air temperature drops because:
They extract heat from the ground, which is at a stable temperature.
An example of an open-loop geothermal water-source heat pump application would be a system connected to a:
Well.
The fluid circulated through the water coil of a geothermal heat pump system is circulated where?
Is circulated through a heat transfer loop buried in the ground.
Some water-source heat pumps contain a separate coaxial coil and water-circulating pumps for heating domestic hot water. The heat for the domestic hot water comes from:
De-superheating the hot gas leaving the compressor.
Water and refrigerant flow through the coaxial coil:
In opposite directions.
Most pond and lake water would not be suitable for an open-loop system because:
It contains too many minerals and contaminants that would lead to scale buildup inside the system.
A water-source system that gets its water from a well and does not reuse the water is:
An open-loop system.
Geothermal heat pumps get most of their heat from:
The ground.