Which type of humidifier needs to be cleaned more than once a year?
A) Evaporative B) Vaporizing C) Steam D) Atomizing
[Ques. 2] How does certification affect heating equipment in the United States?
A) All heating equipment undergoes voluntary testing and certification by accredited testing agencies.
B) All gas appliances are exempt from certification but must be tested by an accredited testing agency.
C) Only electric heating equipment is required to have testing or certification by an accredited testing agency.
D) All heating equipment must be tested, certified, or listed by an accredited testing agency.
[Ques. 3] An evaporative condenser:
A) Cools air through the evaporation of refrigerant inside the condenser.
B) Works by evaporating refrigerant to cool the condenser coil.
C) Works by evaporating water to cool the condenser coil.
D) Is really just another name for evaporator.
[Ques. 4] The advantage of the backward-curved centrifugal fan over the forward-curved centrifugal fan is that:
A) Backward-curved fans operate at lower RPM.
B) Backward-curved centrifugal fans are well suited for small airflow quantities.
C) Backward-curved fans are normally quieter in operation.
D) Backward-curved fans are non-overloading.
[Ques. 5] What happens if the steam trap at the outlet of a heating coil is stuck in the closed position?
A) Steam flow through the coil will stop and the air temperature will be too low.
B) Steam flow through the coil will be excessive and air temperatures will be too high.
C) The steam coil will flood with condensate water.
D) The boiler will stop producing steam.