Ch3 Plumbing Flashcards
Pipes Rated by Tickness
Type K - underground
Type L - Medium (supply lines)
Type M - Thinner (carry condensation)
Type DWV - Used for drains and vents low pressure
*Bring Water to the Ground Slowly
Soil slowly filters
Fast = erosion
Roof and parking drainage - gutter or roof drain
green roof - slows
blue roof - create pond on roof returns water slowly
Plastic Pipe
More common than copper
Less friction
Smaller buildings - not enough fittings yet
*Supply and Waste Water Never Meet
Use air gap to separate
Health and Safety
Back Flow Preventer
If water backs up - mechanism switches to block water and pull in air instead.
Danger is negative pressure could be caused by fire hose and suck back dirty water. - Use vacuum breaker to prevent
Valves
Gate Valve
Glove Valve
Check Valve
Gate Valve
Maintenance shut offs - lots of turning
Min friction b/c controls a lot down stream.
Globe Valve
Faucets
Little turning
More friction - 1 thing down stream.
Check Valve
Backflow Preventer
Water moves one direction
Prevent building to building contamination.
P
(pressure in psi) = 0.433 x H (height)
0.433 - constant converts psi to height, inches to feet
Fixture - 4-20 psi min
50-75 psi in water main
Water seeks its own level
Vault Ball Valve
Replace Gate Valve
Black Water
Human waste or food waste
Lavatory
Sink
How high can fixture be if needs min 12 psi if 25 psi entering building
25-12=13
P=.433xH
13=.433xH
H=30’ (kinda typical)
If higher than 30’ pump water to tank on roof
Can pump to every tenth floor to prevent super high presure
Expansion Loop
B/c hot water pipes expand and contract
Inch worm looking bump
h = .5 length
Welded joint handle expansion
*We size pipes by pressure and flow.
Assuming not all fixtures will be on at same time
Use “Fixture Units” instead of total sum of gal/min and psi of all fixtures.
*Hot Water Heating
140 kitchen and laundry
110 shower
105 hand washing
Trap and Vent
Keeps smells from entering room instead go out exhaust (“sewer gases”)
Vent also keeps trap from being siphoned empty
Water Use (1970 numbers)
Toilets 45%
Bathing 30%
Laundry 20%
Drinking / Cooking 3%ish
Irrigation
Swimming Pool
Car Wash
- Gray water can be reused
- Bathing can go to toilets
- Laundry can go to irrigation
Drains and Traps
Old traps no longer to code
- S trap no vent
- crown - vent (vent over trap prone to clogging)
- Ball trap - also clogging prone
- Drum Trap - also clogging issue
Allowed Traps
- Bottle Trap
- P Trap
Grease Interceptor
Grease floats to top cleaner water pulled from bottom
Repeat in second compartment
Then send to sewer
*Vents
Stack Vent - over soil or waste stack for gas
Waste Stack - gray water
Soil Stack - black water
Vent Stack - no stack below, for gas
Branch Vent - non vertical vent connecting to stack vent from other fixture
Clean out - access point at 90 degree angles
Sometimes two fixtures can share depending on code and interpretation.
*Septic Systems
25% of US don’t have access to sewer system
Scum floats to top, water at bottom like grease int.
Percolation Test - how long it takes water to be absorbed into soil
If don’t have enough land or percolation bad might not be able to build on site.
Could Build mound of good soil
*Can Capture Rain Water
Not common b/c water available from point sources
Use if low access to point source and no access to municipal
Need catchment system, cistern, and get water high up
First X gallons to run off catchment area most dirty - bird poop, have to filter, or divert X gallons
