UNIT 40 REVIEW QUESTIONS ANSWER KEY GO BACK TO INDEX
40-1) What is a communicating control system?
40-2) Explain the difference between the way a relay logic control system operates and
the way a communicating control system operates.
40-3) How can a two stage heat pump be controlled by only four wires?
40-4) What is a communicating protocol?
40-5) List two open protocols.
40-6) What are the four wires used in a common four-wire communicating system?
40-7) How do some communicating systems operate with only two wires between the
indoor blower and the condensing unit?
40-8) Why do communicating control boards often have terminals for traditional 24 volt
controls? To allow communicating equipment to be connected using a traditional
40-9) What type of wire should be used for connecting components of a communicating
control system?
40-10) What is the cause of most communication errors?
40-11) How can a service technician learn what problems a communicating system has
been experiencing?
40-12) Why is the manufacturer’s installation and service literature critical when working
with communicating systems?
40-13) How does a communicating thermostat know what type of equipment is
connected to it?
40-14) What applications are wireless communicating thermostats particularly well
suited for? Any application that uses multistage or modulating technology can benefit
40-15) How do communicating components determine which commands are for them
and which commands are for other devices connected to the network?
40-16) Why are communicating controls particularly well adapted for modulating
capacity systems?
40-17) How can a technician force a system to scan the system and re-learn the
components connected to it?
40-18) Why are communicating controls particularly well adapted for zone control
systems? Communication makes it possible for the variable capacity equipment to
40-19) What type of zone control to some communicating ductless mini-split systems
use? Variable refrigerant velocity systems have multiple indoor coils connected
40-20) Explain the concept of interoperability.
40-21) Discuss the difference between a proprietary system and an open system.
Proprietary systems follow their own unique protocol that is licensed and