Water Supply Systems Flashcards
6 cards from real Plumbing 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 purpose of a tempering valve (mixing valve) on a water heater?
Answer: To blend hot and cold water to deliver water at a safe temperature
A tempering valve blends hot and cold water to deliver water at a pre-set safe temperature (typically 120°F) to prevent scalding.
What is cross-connection in a plumbing system?
Answer: A physical link between potable water and a non-potable source
A cross-connection is any physical connection between potable (drinking) water and a non-potable source that could allow contamination of the drinking water supply.
What is the recommended setting for a residential water heater thermostat to balance energy efficiency and safety?
Answer: 120°F
120°F (49°C) is the EPA-recommended setting that balances energy efficiency, Legionella prevention, and scald protection for most households.
What is the function of the anode rod in a tank-type water heater?
Answer: To sacrifice itself to corrosion, protecting the tank lining
The anode rod (sacrificial anode) is made of magnesium or aluminum and corrodes preferentially to protect the steel tank lining from rust.
What does a pressure and temperature (P&T) relief valve on a water heater do?
Answer: Automatically releases water if pressure or temperature exceeds safe limits
The P&T relief valve is a critical safety device that automatically opens to release water and pressure if the tank exceeds safe temperature (210°F) or pressure (150 psi) limits.
What is the purpose of a check valve in a water supply system?
Answer: To allow water flow in only one direction
A check valve allows water to flow in only one direction, preventing backflow that could contaminate the supply system or damage equipment.