Preventive Maintenance Procedures Flashcards
7 cards from real PC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Preventive Maintenance Procedures flashcards as text
A plumber performing scheduled PM on a commercial building finds that a floor drain trap has evaporated dry. What is the correct remedy?
Answer: Pour water into the trap and consider installing a trap primer
Refilling the trap and installing a trap primer ensures the trap stays sealed to prevent sewer gas from entering the building.
What tool is most appropriate for performing a preventive maintenance inspection of a building's underground drain lines?
Answer: CCTV sewer inspection camera
A CCTV camera allows visual inspection of buried drain lines to detect cracks, root intrusion, offsets, and buildup without excavation.
During PM on a commercial dishwasher, the plumber notices the booster heater is not raising rinse water to the required 180°F. Which plumbing component should be checked first?
Answer: The tempering valve or mixing valve supplying the booster heater inlet
A tempering or mixing valve blending cold water into the supply line can reduce incoming temperature below what the booster heater can raise to 180°F.
What is the significance of the 'first-draw' test during preventive maintenance of a building's plumbing for lead and copper compliance?
Answer: It captures water that has been in contact with pipes and fittings after a stagnation period
First-draw sampling captures water stagnated in pipes, which has the highest contact time with lead solder or copper, revealing actual exposure risk.
When performing a PM pressure test on a newly repaired section of gas piping before re-energizing, which test medium is required by most codes?
Answer: Air or nitrogen at a test pressure exceeding operating pressure
Gas piping must be pressure tested with air or an inert gas like nitrogen—never with gas itself—to safely identify leaks before the system is placed in service.
A preventive maintenance inspection of a pressure-reducing valve (PRV) shows downstream pressure is 20 PSI higher than the set point. What is the most likely cause?
Answer: The PRV seat is worn or debris is preventing it from fully closing
A worn seat or trapped debris holds the PRV partially open, allowing higher-than-set pressure to pass through to the downstream system.
During scheduled PM, a plumber identifies a water softener that is not regenerating on its set schedule. What is the first component to check?
Answer: The brine tank salt level and injector nozzle
Low salt or a clogged injector nozzle are the most common causes of failed regeneration cycles and should be checked before other components.