Answer Key With Short Explanations
1. B — Excessive pressure can damage plumbing components and fixtures
Residential water pressure that is excessively high can stress valves, supply lines, fixtures, and appliances. A pressure-reducing valve may be necessary.
2. B — Reduce excessive incoming water pressure
A PRV reduces high municipal supply pressure to a safer pressure for the home's plumbing system.
3. A — Corrosion or previous leakage
Green or blue deposits around copper piping and fittings can indicate oxidation, corrosion, or evidence of past or ongoing leakage.
4. B — Internal corrosion restricts water flow
Galvanized steel piping commonly corrodes internally as it ages. The buildup can reduce the effective inside diameter and restrict water flow.
5. B — Prevent contaminated water from being drawn into the potable water supply
Backflow protection helps prevent contaminated water from being siphoned backward into the drinking-water system.
6. C — Recommend evaluation and likely replacement of the water heater
Active leakage from the tank itself combined with significant corrosion commonly indicates tank failure rather than a minor repairable condition.
7. B — Reduce galvanic corrosion
When certain dissimilar metals are directly connected, electrochemical reactions can accelerate corrosion. Appropriate dielectric separation can reduce this problem.
8. B — A possible supply restriction or inadequate water-supply capacity
A significant flow reduction when multiple fixtures operate can indicate restricted piping, inadequate supply sizing, or another water-delivery problem.
9. B — Combustible materials stored against or immediately adjacent to the appliance
Combustible materials near a fuel-fired appliance can create a fire hazard and interfere with safe operation and servicing.
10. B — Absorb thermal expansion as water is heated
Water expands when heated. In a closed plumbing system, an expansion tank provides space to accommodate that increased volume.
11. A — A localized restriction in that fixture's drain
If other fixtures drain normally, the problem is more likely near the affected fixture rather than in the building's main drain.
12. B — Pipe rupture due to expansion of freezing water
Water expands as it freezes. This can create enough pressure inside piping to split the pipe or damage fittings.
13. B — Repair the leak and evaluate the extent of moisture-related damage
The source of the moisture must be corrected, and surrounding materials should be evaluated for deterioration or other moisture-related problems.
14. B — Prevent contaminated drain water from siphoning back into the dishwasher
An air gap provides physical separation that helps prevent wastewater from backing or siphoning into the dishwasher.
15. B — It has a history of premature failures and leakage concerns
Polybutylene piping has a documented history of leakage and fitting/pipe failures and should be identified when observed.
16. B — Unexplained moisture staining with elevated moisture readings near plumbing
Visible staining combined with elevated moisture readings provides evidence that an active or recent concealed leak may be present.
17. B — Pressure tank or pressure-control system
Rapid pump cycling can occur when a pressure tank has lost its proper air charge or when other components of the pressure-control system malfunction.
18. B — Allow contamination of the potable water supply
A cross-connection creates a potential pathway for contaminated or non-potable water to enter the drinking-water system.
19. A — Sudden stopping of moving water in the supply piping
When a fast-closing valve abruptly stops flowing water, the resulting pressure wave can cause banging or hammering in the piping.
20. B — The septic system may be failing and requires further evaluation
Surfacing sewage or effluent around a drain field is a significant sanitation concern and can indicate a malfunctioning or overloaded septic system.