water dist quiz Flashcards
a pH level of 4 indicated that the substance is?
acidic
water is considered to be a universal solvent because
more things dissolve in water than in any other solvent
the arterial loop dist system used by municipalities is installed for areas with:
heavy demand on the system
the tree system of water dist makes it difficult to:
supply good water to all parts of the system
changes of direction or elevation in water dist networks are protected from disconnection by:
thrust blocks and anchors
if transmission pipes are rapidly drained without admitting air to the system:
the pipe may collapse from effects of vacuum
a gooseneck on a water service is installed to provide for:
flexibility of the pipe as ground settles after backfill or moves from frost
the corporation curb cock is placed on or near the property line so:
the utility employee doesnt have to trespass on private property
drilling the corporation curb cock for a water service is:
discouraged by the AWWA
if a water service is to be placed in the same trench as the building sewer, the trench:
should be excavated with a raised portion on one side for the water service pipe
if a check valve or backflow preventer is installed to protect a water service pipe that is suitable for cold water only, the building dist system becomes a:
closed water system
the shut off valve placed at the entry point of a 3/4” or 1” water service is allowed to be:
a stop and drain valve
a water test for a water dist system may be done with:
potable water only
what is the reason for having a recirculation line on the hot water dist. line?
to supply hot water to the furthest fixtures immediately
if you were to rough in a back of WC, could you have one shut off valve to serve the bank?
no, one valve is required per WC
ballcock valves come in all shapes and sizes. what is the most important fact about them?
they must be of the anti-siphon type
what methods are used to drain the water in the dist lines in an unheated building?
slope the lines to drain or blow out the lines
the only time you can interconnect public and private water systems is:
it cannot ever be done
when testing water dist systems, the:
test will be an air test at 100 psi for 2 hours
the max and min pressure in a water dist system is:
550 kPag and 200 kPag
a pressure reducing valve is needed when the pressure exceeds ____kPa
550
the higher the pressure in a water dist system, the ______ the flow
noisier
water meters are used for:
metering water for consumption, detecting leaks in the system and metering certain fixtures
a meter bypass must be installed if the meter is larger than ____”
1-1/2”
the information needed for sizing water dist systems is:
d. pressure at the cc, velocity, distance from the main to the farthest faucet and difference in elevation from the main to the highest faucet
the pressure at the curb cock (CC) will not be the actual pressure used for sizing because
the elevation from the curb cock to the highest point must be considered
when sizing the water service, you will size it according the the ____ FU
total
in a gas-fired HWT, the largest volume of hot water is located:
at the top due to the density factor
HWT are usually rated for a max working pressure of ____psi
150psi
the electric hot water tank has an _____ rod since it may be exposed to corrosive water
anode
the lowest opening in a hot water tank is for _____ valve
drain
the HWT dip tube is for directing the ___ water down to the bottom of the tank
cold
the max temp. allowed in a hwt is ____ F
210 F (99 C)
an indirect service hwt is usually heated by ____ water
hot
after completing an installation of a complete water dist system you ____ all the lines, including the clothes washer and dishwasher lines
flush