Why are thermostatic expansion valves often used as the outdoor ...

[kwoodring]

Why are thermostatic expansion valves often used as the outdoor metering device for the heating cycle?
 
  A) TEVs can be adjusted in the field to match the heat pump's performance with the climate it will be operating in.
  B) TEVs are easier to install on the outdoor coil.
  C) TEVs allow the system pressures to equalize in the off cycle, allowing the use of low starting torque compressors.
  D) The TEV can modulate the refrigerant flow over the wide range of temperatures experienced in the heating mode.

Question 2

What air property is measured in grains?
 
  A) The weight of air.
  B) Wet-bulb temperatures.
  C) Grains are used to measure the amount of water in the air.
  D) Relative humidity.

[okolip]

Answer to Question 1

D

Answer to Question 2

C

[kwoodring]

TYSM

[tanna.moeller]

Gracias!