The primary control for all HVACR functions in a direct digital control (DDC) system is:
A) A multistage thermostat.
B) A computer.
C) A relay pack.
D) Not necessary. DDC systems do not use primary controllers.
B
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Answer the following statements true (T) or false (F)
1. Nailing flanges are only provided in steel windows. 2. Most windows are shop-glazed so that they arrive at the construction site in a fully assembled condition. 3. A stool is used in a window in the building's interior. 4. In a stick-built glass curtain wall, the mullions are erected first and the rails are inserted between them. 5. A typical glass curtain wall is provided with weep holes to drain infiltrating water even though it is sealed from both the inside and the outside with gaskets or tapes.
Congress charged the Environmental Protection Agency (EPA) to protect which of the following parts of the environment?
A) land B) air C) water systems D) all of the above
When long straight runs of rigid tubing are required, it may be necessary to install an expansion loop or an expansion offset to absorb the movement. Another alternative is to install an expansion ____ capable of absorbing the movement.
a. regulator b. compensator c. barometer d. overflow
Distillation
