060201a Water Distribution Flow and Water Heaters Flashcards
What is the reason for having a recirculation line on a hot water distribution line?
To supply hot water to the furthest fixtures immediately
Ballcock valves come in all shapes and sizes. What is the most important factor about them?
They must be of the anti-siphon type
Installing a check valve on a water service near the house shut-off valve…
Creates a closed water system
Psi and time limit for testing a water distribution system?
100 psi for 2 hours
Maximum pressure at the fixture in a water distribution system?
550 kPa (80psi)
A meter bypass must be installed if the meter is…
Larger than 1 1/4”
Minimum water service pipe?
3/4”
Best form of backflow prevention?
Air gap (2x spout diameter no less than 1”)
An air break must be a minimum of…
1 pipe diameter or minimum 1”
Ideal test for potable water lines?
Water test (100 psi for 2 hours)
Max lead content when soldering water distribution lines?
0.2%
Minimum amount of shut offs when constructing a bypass?
3
A recirculation line is required when the run of pipe exceeds _____ or _____.
30 metres or 4 stories
In buildings other than single family or multi family dwellings these should be placed on every fixture, or at least located to isolate the water serving that room?
Isolation valve
Expansion tanks are required on these kind of water distribution systems?
Closed system
The addition of a check valve in a water distribution system would make the system a…
Closed system
This type of copper may not be bent
Type M
These kind of valves should be used when constructing a bypass because their full flow design reduces pressure loss?
Gate or ball valves
Most commonly installed water meter size for residential water use measurement?
5/8”
5/8” meter spacing requirement?
12” (300mm)
3/4” water meter spacing requirement?
14” (350mm)
What temperature should a hot water heater be set at?
140°F (60°C)
Where should the temperature and pressure relief valve be placed on a hot water heater?
Within 6” of the top of the tank
All dip tubes have a small hole in the top side called this?
Anti-siphon hole
What is the purpose of the anti-siphon hole in the top of the dip tube?
Prevents hot water from being siphoned out during interruption in the cold water supply
Maximum and minimum height off the ground of a hot water heater pressure relief valve outlet pipe?
12” max 1” min
A better type of relief device incorporates a __________ or _____ _____ that opens at a temperature of ___ °C ?
Bellows, bimetal disc, 99°C (210°F)
The control found on most gas-fired hot water heaters incorporates a thermostatic sensing element into its operation. The thermostatic sensing element is of what design?
Rod and tube
This must be installed on the cold water supply if a hot water tank is supplied with cold water near the bottom?
Vacuum breaker
Maximum temperature allowed in a hot water tank?
210°F (99°C)
An energy cut-off (ECO) can be used instead of a __________ ?
Temperature relief valve
Hot water tanks are usually rated for a maximum working pressure of _____?
150 psi
