Water Supply Systems Flashcards
6 cards from real 306A practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Water Supply Systems flashcards as text
What is the recommended maximum length of a dead-end (dead leg) in a hot water distribution system?
Answer: 3 m
Dead legs in hot water systems should not exceed approximately 3 m (10 feet) to prevent stagnant warm water that promotes Legionella growth and wastes water while users wait for hot water to arrive.
What is the purpose of a hot water recirculation system?
Answer: To provide near-instant hot water at fixtures far from the heater by continuously circulating hot water
A recirculation system uses a pump and return line to keep hot water moving through the distribution piping, so hot water is available almost immediately at remote fixtures without wasting water waiting for it to arrive.
When soldering copper water supply joints, what flux type must be used for potable water systems?
Answer: Water-soluble flux approved for potable water
Only water-soluble flux specifically approved for potable water systems may be used. Acid-based or petroleum-based fluxes can contaminate the water supply and corrode the copper over time.
What solder is required for joints in potable water supply piping in Canada?
Answer: Lead-free solder (95/5 tin-antimony or similar)
Lead-free solder is mandatory for all potable water supply piping in Canada to prevent lead contamination. Common lead-free formulations include 95/5 tin-antimony or tin-silver alloys.
What is the minimum insulation R-value required for hot water supply piping in most Canadian energy codes?
Answer: R-3 to R-4 depending on pipe size
Canadian energy codes generally require R-3 to R-4 insulation on hot water supply piping, depending on the pipe diameter, to reduce heat loss and conserve energy.
What is the purpose of a check valve on the cold water inlet to a water heater?
Answer: To prevent hot water from migrating back into the cold water supply
A check valve on the cold water inlet prevents thermosiphoning, where heated water rises back into the cold water line, causing energy waste and potentially delivering hot water to cold-water fixtures.