To control static pressure in the air ducts a differential pressure controller is installed. How does the controller control static pressure?
a) By increasing air temperature
b) By decreasing air temperature
c) By modulating the damper on the suction side of the fan
d) By modulating the damper on the discharge side of the fan
e) By grounding the ductwork and carrying the charge to a battery
Answer: C
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Power Engineering
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