Author Question: Describe the operation of a dual fuel heat pump operating below the balance point. What will be ... (Read 63 times)

TVarnum · **on:** Jul 26, 2018

Describe the operation of a dual fuel heat pump operating below the balance point.

What will be an ideal response?

Question 2

Describe the operation of a heat pump with electric strip heat operating below the balance point.

What will be an ideal response?

mceravolo · **Reply #1 on:** Jul 26, 2018

Answer to Question 1

In a dual fuel system, the furnace operates below the balance point and the heat pump shuts off. When a gas or oil furnace is used for supplemental heat, the heat pump shuts off when the furnace comes on because the hot air from the furnace passing over the indoor coil would cause extremely high head pressures in the heat pump.

Answer to Question 2

An air to air heat pump will operate continuously when the outdoor temperature is below the balance point. The auxiliary heat is turned off before the first stage of the thermostat is satisfied, so the heat pump continues to run. Since the refrigeration system can-not provide enough heat below the balance point to meet the load, the first stage heating thermostat will not be satisfied. The auxiliary heat will cycle on and off to maintain a temperature just below the thermostat set point.