Which of the following problems could occur if a humidifier is not regularly cleaned and checked for ...

Which of the following problems could occur if a humidifier is not regularly cleaned and checked for operation?
 
  A) Excessive dryness B) Mold growth
  C) Nickel in the water supply D) CO poisoning

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[Ques. 2] How much moisture can air hold when it is heated to 70F?
 
  A) 110 grains per pound B) 50 grains per pound
  C) 105 grains per pound D) 200 grains per pound

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[Ques. 3] Beginning in 2013, which region in the United States will have the highest minimum AFUE rating?
 
  A) The North B) The South
  C) The Southwest D) All regions share a minimum AFUE rating.

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[Ques. 4] The major components of an air-handling unit include:
 
  A) Compressor, evaporator, and condenser.
  B) Heating and cooling coils and electric heat strips.
  C) Air compressor, water separator, and air tank.
  D) Fan and motor, heating and cooling coils, air filter, dampers.

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[Ques. 5] Water treatment is necessary to protect the system components against:
 
  A) Scale, corrosion, and fouling. B) Hypothermia, outgassing, and corrosion.
  C) Freezing, evaporation, and sublimation. D) Fouling, freezing, and evaporating.