Deck 24: Heat Sources for Water Heaters and Ancillary Piping

Question 1

Water heater efficiency is rated by the ____________________, a percentage of how much of the purchased fuel energy is converted into usable hot water.

A)BTU
B)HSPF
C)energy factor
D)therm

Answer 1

C

Question 2

The temperature and pressure relief valve must be located within the top ____ inches of the water heater.

A)4
B)6
C)8
D)12

Answer 2

B

Question 3

The biggest difference between electric water heaters and fuel-fired water heaters is that electric water heaters have no need for combustion air, a(n)____________________ chamber, or a flue pipe.

A)thermal
B)combustion
C)insulation
D)element

Answer 3

B

Question 4

In a(n)____________________ system, the pump runs only when the differential controller senses that the solar collector is hotter than the tank temperature.

A)drainback
B)direct
C)indirect
D)differential

Question 5

Lowering of water temperature to less than 122°F can allow for the growth of Legionella bacteria, which is the cause of Legionnaire's Disease.

Question 6

An electrically energized heating element that is not submerged in water will overheat and fail in a matter of seconds.

Question 7

Which type of heat transfer occurs in a gas-fired water heater tank when the burner is not firing and tends to move hot water toward the top of the tank?

A)conduction
B)convection
C)radiation
D)emissivity

Question 8

Which type of solar water heater uses a separate loop to transfer solar energy from the collector to a heat exchanger?

A)drainback
B)direct
C)indirect
D)differential

Question 9

What are two goals that can be accomplished by installing multiple water heaters?

Question 10

In a gas-fired water heater, the flame should never come in contact with the surface of the tank.

Question 11

What is the term that refers to a temperature spread in a water heater tank that results in the first water out of the tank being too hot to be safe?

A)stacking
B)overheating
C)convection
D)conduction

Question 12

Two factors that influence the selection of a water heater are:

A)color of tank and type of fuel available
B)type of fuel available and energy costs associated with fuel
C)energy costs associated with fuel and time to install
D)time to install and type of fuel available