Book 2 Chapter 12: Building Water Supply Systems

Question 1

Name the three most common upfeed water systems.

Answer 1

Direct pressure system
Tankless constant pressure system
Pressure system with pneumatic tank

Question 2

The pressure in the building plumbing system should not drop below _________at any location.
A) 150kPa (20psi)
B) 175kPa (25psi)
C) 250kPa (35psi)
D) 300kPa (42psi)

Answer 2

B) 175kPa (25psi)

Question 3

A pressure switch operates by ________________________ within preset minimum and maximum pressure settings.

Answer 3

Starting and stopping the pump on an intermittent basis to maintain the water pressure in the hydropneumatic (water and air) tank.

Question 4

Temperature relief devices are effective in eliminating which of the following:
A) Scale build-up in the system
B) Flashing of water into steam when faucets are opened
C) Venting air released from water during heating
D) Inadequate heating of the water

Answer 4

B) Flashing of water into steam when faucets are opened

Question 5

An air gap is a _____________ between the free flowing discharge end of a potable water pipe and an open or non-pressure receiving vessel such as a sink or bathtub.

Answer 5

Physical separation

Question 6

The pounding or banging of pipes and shuddering of fixtures cause by a shock wave resulting from a sudden stop of water flow in a pipe results in:
A) Release of entrapped air
B) Pump discharge valve slamming shut
C) Sudden stoppage of flow
D) Water hammer

Answer 6

D) Water hammer

Question 7

The oversized pump can produce _________________________.

Answer 7

Cavitation through the pump and in the surrounding piping.

Question 8

Fusible plugs are made of materials that melt at a temperature of ____________.
A) 99°C (210°F)
B) 150°C (300°F)
C) 125°C (260°F)
D) 225°C (440°F)

Answer 8

A) 99°C (210°F)

Question 9

The RP, DCVA, and the PVB must be verified by a certified backflow tester when:
A) The chief medical officer requires it
B) A city council member requires it
C) The architect requires it
D) The local enforcing water supplier requires it
E) The contractor requires it

Answer 9

D) The local enforcing water supplier requires it

Question 10

The back flow prevention method that consists of two independently acting check valves that close if the supply pressure is lower than the downstream pressure is called:
A) PVB (Pressure Vacuum Breaker)
B) RP (Reduced Pressure)
C) Air gap backflow device
D) Atmospheric Vacuum Breaker
E) DCVA (Double Check Valve)

Answer 10

E) DCVA (Double Check Valve)

Question 11

A hot water mixing valve is a:
A) Four way valve
B) Flow through valve
C) Gate valve
D) Two way valve
E) Three way valve

Answer 11

E) Three way valve

Question 12

The building water supply system which has a storage tank above the highest fixture in the system is called a/an:
A) Constant pressure system with suction tank
B) Updfeed system
C) Downfeed system
D) Direct pressure system
E) Tankless constant pressure system

Answer 12

C) Downfeed system

Question 13

Which of the following statements about non-circulating hot water systems is true?
A) The systems have a return line
B) The systems are used in large residential buildings
C) The systems force large amounts of water to be wasted before hot water is available in each fixture
D) The systems eliminate hot water stagnation
E) The systems contain a different fire recoil element

Answer 13

C) The systems force large amounts of water to be wasted before hot water is available in each fixture

Question 14

Plumbing codes generally limit the highest pressure permissible in plumbing systems to:
A) 350kPa
B) 550kPa
C) 500kPa
D) 600kPa
E) 490kPa

Answer 14

B) 550kPa

Question 15

Temperature relief devices are effective in eliminating which of the following problems?
A) Flashing of water into steam when faucets are opened
B) Water stagnation
C) Scale build-up in the system
D) Inadequate heating of the water
E) Venting off air released from water during heating

Answer 15

A) Flashing of water into steam when faucets are opened

Question 16

The backflow prevention method which consists of two independently acting check valves with an automatic operating pressure differential relief valve located between the two check valves is called:
A) PVB
B) Reduced pressure principle device
C) Air gap back flow prevention
D) Atmostphere vacuum breaker
E) Double check valve

Answer 16

B) Reduced pressure principle device

Question 17

Hot water mixing valves are controlled by an Aquastat connected to the:
A) Cold water supply line
B) Hot water return line
C) Low temperature side of the valve
D) High temperature side of the valve
E) Blended water return line

Answer 17

C) Low temperature side of the valve

Question 18

A flushometer valve:
A) Measures the amount of water discharged from water closets per day
B) Is operated by vacuum
C) Is only used on urinals
D) Records the number of plumbing fixture flushes per day
E) Provides an air gap and a vacuum breaker between potable water and unsanitary systems

Answer 18

E) Provides an air gap and a vacuum breaker between potable water and unsanitary systems

Question 19

Water at approximately _________ is required by a kitchen and laundry for sterilization.
A) 60ºC (140ºF)
B) 120ºC (248ºF)
C) 100ºC (212ºF)
D) 90ºC (194ºF)
E) 80ºC (176ºF)

Answer 19

E) 80ºC (176ºF)

Question 20

One of the methods employed to prevent backflow and control the cross connections is the:
A) Air globe
B) Temperature vacuum breaker
C) Reduced temperature principle device
D) Atmospheric vacuum breaker
E) Double check breaker

Answer 20

D) Atmospheric vacuum breaker

Question 21

Most municipal water systems distribute water at pressures between:
A) 550kPa (80psi) and 620kPa (90psi)
B) 450kPa (65psi) and 520kPa (75psi)
C) 350kPa (50psi) and 420kPa (60psi)
D) 250kPa (36psi) and 320kPa (46psi)
E) 150kPa (22psi) and 220kPa (32psi)

Answer 21

C) 350kPa (50psi) and 420kPa (60psi)

Question 22

A typical self-operating temperature regulator consists of a bulb, capillary, and a valve actuating bellows that is filled with a/an:
A) Water
B) Wax
C) Vegetable oil
D) Petroleum fluid
E) Volatile fluid

Answer 22

E) Volatile fluid

Question 23

Most plumbing fixtures need a minimum of _______ water flow pressure.
A) 100kPa (14.5psi)
B) 110kPa (15psi)
C) 90kPa (14psi)
D) 130kPa (19psi)
E) 120kPa (17.5psi)

Answer 23

B) 110kPa (15psi)

Question 24

The atmospheric vacuum breaker has a moving element that should the flow stop and water pressure is lost it __________ and break the siphon effect.
A) Closes to admit water
B) Opens to admit water
C) Opens to admit air
D) Opens to release pressure
E) Closes to admit air

Answer 24

C) Opens to admit air

Question 25

One of the methods employed to prevent backflow and control the cross connections is the:
A) Reduced pressure principal device
B) Atmospheric valve breaker
C) Air globe
D) Double check breaker
E) Temperature vacuum breaker

Answer 25

A) Reduced pressure principal device

Question 26

Fusible plugs are made of materials that melt at a temperature of:
A) 99ºC (210ºF)
B) 125ºC (260ºF)
C) 150ºC (300ºF)
D) 225ºC (440ºF)
E) 90ºC (194ºF)

Answer 26

A) 99ºC (210ºF)

Question 27

The temperature relief device opens when the water temperature rises to approximately:
A) 103ºC (217ºF)
B) 110ºC (230ºF)
C) 105ºC (221ºF)
D) 99ºC (210ºF)
E) 90ºC (194ºF)

Answer 27

D) 99ºC (210ºF)

Question 28

Backflow in a potable water supply is the ________ of water or other liquid, gas, mixture, or other substance into the distributing pipes.
A) Reversal of temperature
B) Reversal of the direction of the normal flow
C) Reversal of pressure
D) Change of pressure
E) Change of temperature

Answer 28

B) Reversal of the direction of the normal flow