Deck 7: Water Pipe Sizing: Main-And-Branch and Individual Run Systems

Question 1

All brands of PEX have a metal crimp ring that holds the fitting in place.

Answer 1

False

Question 2

Water temperature changes due to usage at other fixtures are reduced by using a manifold and individual runs.

Answer 2

True

Question 3

In an individual run system, the header is usually equipped with individual valves for each tube.

Answer 3

True

Question 4

The piping manufacturer's recommended maximum flow velocity through the pipe should be known and honored.

Question 5

One of the advantages of the individual run system is that only a small amount of pipe is needed.

Question 6

Variations in water pressure in a building may be caused by heavy demand on the public mains or by undersized components in the building system.

Question 7

Individual run systems have fewer fittings than main-and-branch systems.

Question 8

The water supply fixture unit concept is used to estimate minimum probable demand in piping systems.

Question 9

Which of the following will cause pressure drop in a piping system?

A) pressure drop at the water outlet
B) head loss due to elevation in the building
C) pipe friction due to flow
D) all of the above

Question 10

PEX is the only piping material allowed to be used in manifold systems.

Question 11

All individual run systems for domestic water supply contain a main supply header and a return header, forming a loop.

Question 12

A water supply fixture unit is based on which of the following traits?

A) actual flow required
B) duration of use of the fixture
C) time between uses
D) all of the above

Question 13

There is a reduced chance of water hammer with individual run systems because there is less water volume and plastic piping is typically used.

Question 14

PEX can be buried directly in a concrete slab.

Question 15

Name three methods of pressurizing the water supply system in a building.

Question 16

Pressure at the base of a column of water H feet high is 0.433(H) psi.

Question 17

A standard practice is to limit the velocity of water in a piping system to less than

A) 8 fps.
B) 9 fps.
C) 10 fps.
D) 11 fps.

Question 18

Which of the following is NOT an example of a pressure boosting system?

A) elevated gravity tank
B) booster pump
C) ejector
D) hydropneumatic tank

Question 19

In a water piping system, it is necessary to estimate the maximum probable flow at all points in the system.

Question 20

If 10 gallons of water were flowing through a 2" diameter pipe and the pipe diameter was suddenly increased,

A) the water's velocity would remain the same.
B) the water's velocity would increase.
C) the water's velocity would decrease.
D) none of the above.

Question 21

List three common applications for individual run systems.

Question 22

Using Table 7-5 in the textbook, a hose bibb in an individual dwelling is equal to how many WSFU?

Question 23

Using Table 7-13 in the textbook, what is the pressure drop for a 25' run of 1/2" PEX tubing if it supplies 1 gpm of water?

Question 24

What is the pressure drop per 100' of PEX tubing if 1 gpm is flowing through a 3/8" diameter line? Use Table 7-13.

Question 25

What is the pressure drop per 100' of PEX tubing if 3 gpm is flowing through a 3/8" diameter line? Use Table 7-13.

Question 26

Using Table 7-10 in the textbook, a $3 / 4''$ 90-degree elbow is equal to how many feet of pipe?

Question 27

Using Table 7-9 in the textbook, determine the friction loss for $3 / 4''$ Type M copper tubing at 4 fps velocity.

Question 28

Using Table 7-5 in the textbook, determine the WSFU rating for a domestic kitchen sink in an individual dwelling unit.

Question 29

Using Table 7-5 in the textbook, a water closet with a 1.6 gpf gravity tank in an individual dwelling is equal to how many WSFU?

Question 30

List two disadvantages of individual run systems.

Question 31

Using Table 7-10 in the textbook, a 3" gate valve is equal to how many feet of pipe?

Question 32

List three advantages of an individual run system.

Question 33

Using Table 7-13 in the textbook, what is the pressure drop for a 200' run of 1" PEX tubing if it supplies 5 gpm of water?

Question 34

Using Table 7-9 in the textbook, determine the velocity in feet per second (fps) for $1^{1 / 2}$ " Type K copper at 2.6 psi/100' pressure loss.

Question 35

Using Table 7-5 in the textbook, what is the minimum branch pipe size that can serve a kitchen group?