home systems
P-Trap
Definition: The curved pipe section under sinks that holds water to prevent sewer gases from entering your home.
A P-trap is the curved section of drainpipe under sinks, tubs, and other fixtures. Its shape holds water that creates a seal preventing sewer gases from entering your home.
How It Works: 1. Water flows through the trap when you use the fixture 2. Some water remains in the curved section 3. This water blocks sewer gases from rising up 4. Each time you use the fixture, water refreshes
Why "P-Trap": When viewed from the side, the pipe resembles the letter "P" (or "U" when looked at straight on).
Why It Matters:
- Blocks toxic and foul-smelling sewer gases
- Required by plumbing codes
- Present under every sink, tub, and floor drain
- Toilets have built-in traps
Common P-Trap Issues:
Clogs:
- Solution: Remove and clean, use a drain snake
Leaks:
- Solution: Tighten connections, replace washers
Dry Trap:
- Solution: Run water periodically
Smell:
Maintenance:
- Run water in unused drains monthly
- Clean hair and debris regularly
- Check for leaks under sinks
- Replace old or corroded traps
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