PDX_11_Plumbing 2

Question 1

Most common water heating type in US.
Residential tanks typ. 40-60 gallons,
50-100 psi,
120-180°F

Answer 1

Storage or tank water heaters

Question 2

Water is quickly heated and sent as needed.
Variable speed pumps.
Save space, but pumps wear out faster.

Answer 2

Tankless water heater

Question 3

Water heated in one spot, stored in another until needed

Answer 3

Circulating water heater

Question 4

Water is supplied to each fixture,
and heated when faucet is turned on.
More efficient, but more upfront cost to install

Answer 4

Instantaneous (inflow) heater

Question 4

Direct solar water heating is often called

Answer 4

Open loop

Question 5

Solar water heating:

Water used is same that’s heated in collectors.
It’s simple & efficient, but subject to freezing.

Answer 5

Direct (open loop)

Question 6

Indirect solar water heating is also called

Answer 6

Closed loop

Question 8

Solar water heating:

Separate fluid, often w/ anti-freeze, collects heat & transferes to domestic hot water system via heat exchanger, which lowers efficiency somewhat

Answer 8

Indirect (closed loop)

Question 9

Solar water heating:

Circulation that relies on gravity and thermosiphoning of heated water.

Simple, low-cost, but must be placed close to collector and point of use.

Answer 9

Passive circulation

Question 10

Solar water heating:

Pumps are used to circulate heat collecting fluid. Costs more, but more reliable and flexible

Answer 10

Active circulation

Question 11

Solar heating System:

Water is heated directly in black tank inside a glazed box, simple but subject to freezing and nighttime heat loss

Answer 11

Batch solar heating system

Question 12

Solar heating System:

Relies on natural movement of hot water to circulate in a passive, open loop system,
storage tanks must be located above collectors.

Answer 12

Thermosiphon

Question 13

Solar heating System:

Open loop system which drains water from collectors @ freezing.
Water is wasted, so best in mild climate

Answer 13

Drain down Solar heating system

Question 13

Solar heating System:

Collector fluid is phase change materials

Answer 13

Phase change system

Question 14

Solar heating System:

Indirect system where water collects heat and pumped into heat exchanger, where coil of domestic hot water is heated.
At low temps pump turns off, and water drained to storage tank

Answer 14

Drain back solar heating system

Question 15

Point of use temperatures:

Therapeutic bath

Answer 15

95°F

Question 16

Point of use temperatures:

Handwashing

Answer 16

105°F

Question 17

Point of use temperatures:

Showers and baths

Answer 17

110°F

Question 18

Point of use temperatures:

Residential dishwashing

Answer 18

140°F

Question 19

Point of use temperatures:

Commercial dishwashing/commercial laundry

Answer 19

180°F

Question 20

Water becomes uncomfortable to the touch above this temperature

Answer 20

110°F

Question 22

Drainage slope for typical effluent waistlines

Answer 22

1/4” per ft.

Question 23

Traps are typically installed within_feet of fixture

Answer 23

2’

Question 23

Waste stack versus soil stack

Answer 23

Waste stack does not carry human waste.

Question 24

Device used in some fixtures to accomplish same thing as trap.

Answer 24

Vacuum breaker

Question 25

The waste stacks connect to this drain at the bottom of the building

Answer 25

Horizontal drain

Question 26

Minimum diameter of a vent

Answer 26

1-1/4”, or half ø of drain it serves, whichever larger.

Question 28

Cleanouts are provided at intersections to allow for maintenance of drain every:

Answer 28

Every 50’ @ < 4”ø pipes.
Every 100’ @ > 4”ø pipes.
Every corner where pipe changes direction more than 45°

Question 29

Manholes occur every ___ feet or where lines change direction.

Answer 29

150’

Question 30

Used when fixtures are lower than the level of the house drain and sewer.

Answer 30

Sump pit

Sewage is collected and pumped to a higher level to flow by gravity into the sewer.

Question 31

Small-scale sewage treatment system, not connected to municipal line

Answer 31

On-site waste disposal system

Question 32

Underground tank where sewage collects. Solid material sits and liquid waters pass on to leach field

Answer 32

Septic tank

Question 32

Underground, poorest chamber where sewage soaks into the surrounding ground until it gets clogged. Then it’s capped at a new one is dug.

Answer 32

Cesspool or seepage pit

Cheapest system but least desirable too

Question 34

Underground, porous chamber where sewage soaks into ground until clogged. Then capped at new one dug.

Answer 34

Cesspool or seepage pit

Cheapest system but least desirable too

Question 35

Like septic-tank-system, but uses anaerobic digestion process
(vs. anaerobic process of septic).
Produces high-quality second effluent, can be sterilized for irrigation.

Answer 35

Aerobic treatment system

Question 36

V-shaped sloping channels in grass,

guide runoff to points for collection and/or disposal

Answer 36

Swales

Question 37

Like manholes, but w/ top grate cover.
Placed @ lowest point of swale,
collect runoff and pass into storm drain system

Answer 37

Catch basins

Question 38

Artificial lake w/ vegetation around perimeter,
designed to contain max expected run off,
then slowly release to storm sewer system

Answer 38

Retention ponds

Question 39

Temporarily stores water, eventually empties to downstream water body

Answer 39

Detention pond

Question 40

Like retention pond except stormwater is directed to groundwater through permeable soils

Answer 40

Infiltration pond

Question 41

Gutter slope range:

Answer 41

1/16” to 1/2” per ft