Plumbing Theory Period 2 (CND) Flashcards
(224 cards)
What is the reason for having a recirculation line on the hot water distribution line?
To supply hot water to the furthest fixture immediately.
If you were to rough in a bank of water closets, could you have one shut-off valve to serve the bank?
No, one valve is required per water closet.
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 distribution lines in an unheated building?
Slope the lines to a drain or blow out the lines.
Installing a check valve on a water service near the house shut-off valve, creates a?
Closed water system.
The only time you can inter connect public and private water system is ?
Never, it cannot ever be done.
When testing water distribution systems, the test will be an?
Air test at 100 psi for 2 hours.
The maximum pressure at the fixture in a water distribution system is?
550 KPag
A pressure reducing valve is needed when?
The pressure exceeds 550 KPag.
The higher the pressure in a water distribution system?
The noisier the flow.
Water meters are used for?
Metering water consumption, detecting leaks in the system, metering certain fixtures and billing purposes.
A meter bypass must be installed in the meter is?
Larger than 1-1/4”
What is the smallest size of service pipe allowed?
3/4”
What is the requirement for size when servicing more than one fixture with the water heater?
3/4”
What are the 3 requirements for using the simplified method of water sizing?
- Separate water services
- The total developed length of this water system measured from the most or furthest fixture to the property line is not more than 90m.
- The minimum static pressure at the water service entry, usually the building isolation valve is not less that 200kpa.
The information needed for sizing water distribution system is?
Pressure at the building isolation, distance from the main to the farthest faucet.
The pressure at the curb cock will not be the actual pressure used for sizing because?
The minimum pressure at the building isolation must be atleast 200kpa.
When sizing the water service, you will?
Size is according to the total cold fixture units.
Residential instantaneous water heaters are designed for?
Low flow rates.
In gas fired hot water tank, the largest volume of hot water is located?
At the top due to the density factor.
Hot water tanks are usually rated for a maximum working pressure of?
150 psi
The electric hot water tank has?
An anode rod since it may be exposed to corrosive water.
Hot water tanks are sized according to the?
Number of building occupants
The lowest opening in a hot water tank is for?
Drain valve