Heat Pumps Flashcards

Which type of heat pump extracts heat from the ground rather than outdoor air?

Answer: Geothermal (ground-source) heat pump

Geothermal heat pumps use underground loops to exchange heat with the earth, which stays at a relatively constant temperature year-round.

When a heat pump is in heating mode and the emergency heat is energized, what happens?

Answer: Only electric resistance strips provide heat; the compressor is locked out

Emergency heat bypasses the heat pump compressor and relies solely on electric resistance heat strips, typically used when the heat pump has failed.

What is a common symptom of a stuck reversing valve in the heating position?

Answer: Both A and C

A reversing valve stuck in heating mode causes the system to heat when cooling is called for, and the outdoor coil may ice in summer because it acts as an evaporator.

What is the purpose of the check valves used in a heat pump refrigerant circuit?

Answer: Redirect refrigerant flow so both the indoor and outdoor coils can act as either evaporator or condenser

Check valves route refrigerant around the metering devices depending on the direction of flow, allowing a single bidirectional circuit.

What outdoor temperature indicates a heat pump may need a 'cold climate' or variable-speed model to remain effective?

Answer: Below 0°F

Standard heat pumps lose significant capacity below 32°F, while cold-climate models maintain heating capacity down to -13°F or lower.

What does HSPF2 measure for a heat pump?

Answer: Heating efficiency measured as total heat output divided by total electrical energy over the heating season

HSPF2 (Heating Seasonal Performance Factor 2) rates heating efficiency; higher values indicate more efficient heating performance.