How many wires are needed for a communicating control system to control a three-stage heat, two-stage cool heat pump?
A) Four wirestwo for power and two for communication
B) Nine wiresone for each stage plus reversing valve and power
C) Five wiresone for each stage heat and cool
D) No wires are required because communicating systems are wireless.
Question 2
What does a roll-out switch do?
A) It shuts off the gas valve if flames are sensed outside the combustion area.
B) It allows the combustion components to be rolled out of the combustion chamber.
C) It ensures proper clearance between the furnace and nearby walls.
D) It checks to make sure the blower has not rolled out of position on the unit.
Heat Index
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