The purpose of the "freeze-stat" temperature controller used with hot water coils is to
a. Close the outside air dampers and stop the fan if the heat source fails or the low limit temperature controller malfunctions
b. Prevents coil freeze-up by increasing the hot water flow through the coil to a maximum if the outside air temperature is too low
c. Increase the heat source temperature if the outside air temperature decreases
d. Shut off all water flow to the coil if a freeze condition is detected
e. Increase the fan output if the return air temperature is too low
Answer: A