Journeyman Plumber ExamDrainage, Waste, and Venting (DWV) SystemsHard
A plumber is installing a grease interceptor for a restaurant kitchen. Which of the following statements about grease interceptor installation is FALSE?
- AIt must be vented in accordance with plumbing code requirements.
- BIt should be connected in series with other interceptors for increased efficiency.
- CIt should be sized based on the anticipated flow rate from the fixtures it serves.
- DIt must be readily accessible for cleaning and maintenance.
Show answer & explanationAnswer & explanation
Correct answer: B. It should be connected in series with other interceptors for increased efficiency.
Grease interceptors should never be connected in series. Connecting them in series would impede flow, increase pressure drop, and not significantly improve efficiency, potentially causing system issues. Each interceptor is designed to function independently. The other statements are true and critical for proper installation and function.
Why the other options are wrong
- A. Proper venting is essential for any drainage device to ensure hydraulic efficiency and prevent trap siphonage.
- C. Sizing based on flow rate and grease retention capacity is fundamental for effective interceptor operation.
- D. Accessibility is crucial for the frequent cleaning required of grease interceptors.
Grease Interceptor Installation
The correct placement, connection, and sizing of a device designed to separate grease and oils from wastewater before it enters the public sewer system.
- Prevents grease buildup in sewer lines.
- Requires frequent cleaning.
- Must be properly sized and vented.
- NOT to be connected in series.
Memory trick: Grease trap's job, keep it clean, no series, less scene!