What is the purpose of the expansion tank?

What is the purpose of the expansion tank?
 
  A) To allow room for extra water
  B) To allow for water volume changes due to temperature change
  C) To reduce the water temperature by expansion
  D) To provide pressure for the water system

 Q. 2

How does the technician know which way to install a disposable panel air filter?
 
  A) The arrow on the side of the filter points towards the entering air side.
  B) The side of the filter that is reinforced should be installed in the entering airflow.
  C) The arrow on the side of the filter points in the direction of airflow.
  D) Most disposable filters can be installed in either direction.

 Q. 3

Compared to air heating systems, hydronic heating systems
 
  A) Automatically add humidity as well as heat B) Are normally less expensive to install
  C) Can be more easily used for air conditioning D) Are normally more expensive to install

 Q. 4

What do modern hydronic systems use to circulate the hot water?
 
  A) convection B) gravity C) pumps D) fans

 Q. 5

How will an extremely dirty air filter affect the amp draw of a PSC centrifugal blower motor?
 
  A) The fan motor current is not affected by the air filter.
  B) It will cause the motor current to increase because it is working harder to move the air through the system.
  C) The motor will begin to draw negative amps due to the magnetic-thermal motor winding reaction to the increased temperature caused by reduced airflow.
  D) It will cause the motor current to decrease because the fan will be moving less air.

 Q. 6

With the system operating, a technician gets a reading of 20 volts between the L1 and T1 terminals at the contacts of the contactor. This tells the technician that:
 
  A) The contacts are defective because they have a measurable voltage drop.
  B) The compressor is defective.
  C) The contactor is operating correctly.
  D) The transformer is defective because the voltage should be 24 volts.