Plumbing Flashcards
7 cards from real NHIE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Plumbing flashcards as text
What is the maximum temperature a residential water heater should be set to in order to prevent scalding?
Answer: 120°F
The recommended maximum water heater temperature is 120°F to prevent scalding while still being hot enough to inhibit Legionella bacteria growth.
A home inspector identifies copper supply pipes with a greenish-white crust on the outside of soldered joints. What does this indicate?
Answer: Active or past pinhole leaks or weeping at the solder joint
Greenish-white mineral deposits (verdigris) on copper pipe joints indicate moisture has escaped, signaling a pinhole leak or failing solder joint.
Which material requires a dielectric union when connected directly to copper pipe?
Answer: Galvanized steel pipe
Galvanized steel connected directly to copper creates a galvanic cell that accelerates corrosion; a dielectric union electrically isolates the two metals.
What is the function of a pressure-reducing valve (PRV) installed on the main water supply?
Answer: It reduces incoming municipal water pressure to a safe range for household plumbing
A PRV reduces high incoming municipal water pressure (often 80-150 psi) to a safe household range of 40-80 psi to protect fixtures and pipes.
An inspector notes that a floor drain in a basement utility room has no visible water in the trap. What is the recommended correction?
Answer: Pour water into the drain to replenish the trap seal and prevent sewer gas entry
Infrequently used floor drains can lose their trap water seal through evaporation; pouring water into the drain restores the seal that blocks sewer gases.
What type of pipe fitting is used to change direction 90 degrees on a DWV drain line while minimizing flow restriction?
Answer: Long-sweep 90-degree elbow
A long-sweep 90-degree elbow has a gradual curve that minimizes turbulence and resistance in drain flow, making it the preferred fitting for horizontal DWV runs.
Which condition indicates a sump pump system requires attention during a home inspection?
Answer: The discharge pipe terminates near the window well of the basement
Discharging sump water near a window well or back toward the foundation defeats the purpose and can reintroduce water into the basement.