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Author Question: The primary control for all HVACR functions in a direct digital control (DDC) system is: A) Not ... (Read 120 times)

nenivikky

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on: Jul 24, 2018
The primary control for all HVACR functions in a direct digital control (DDC) system is:
 
  A) Not necessary. DDC systems do not use primary controllers.
  B) A computer.
  C) A relay pack.
  D) A multistage thermostat.

Question 2

Soot accumulation on the heat exchanger is:
 
  A) Not possible with a gas furnace.
  B) A natural protective layer for the inside of the heat exchanger.
  C) Caused by incomplete combustion.
  D) Normal over a period of years.


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thall411

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Reply #1 on: Jul 24, 2018
Answer to Question 1

B

Answer to Question 2

C


nenivikky

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Reply 2 on: Jul 24, 2018
Wow, this really help

daiying98

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Reply 3 on: Yesterday
:D TYSM

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