What Is a P-Trap, Its Purpose, and How It Works?

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Even if you aren’t a plumber by trade, you’ve probably seen the u-shape piece of piping under your kitchen or bathroom sink. This is a specific piece of plumbing equipment called a P-trap, and it is a necessary part of your home’s plumbing system. A P-trap that is improperly installed or serviced can cause a number of problems for the sink it is attached to as well as other systemic problems, so it’s always best to hire trained Denver plumbers for P-trap work, like the ones at Bell Plumbing and Heating. If you need help with a P-trap, be it for installation, repair, maintenance or replacement, call us right away.

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What Is the Purpose of a P-Trap?

So why is a P-trap part of your plumbing? There are three main reasons:

  • Plumbing codes require a P-trap be installed anywhere there is an open drain line that expels wastewater into a drain waste-vent system.
  • The P-trap traps solids that can clog the drain or sewer line.
  • The P-trap stops sewer gases from backing into your home through the drain line.

How It Works

P-traps in a kitchen or sink will work the same way, but they do have different sizes. Bathroom sink P-traps are typically 1 ¼ inches in diameter and kitchen sink P-traps are typically 1 ½ inches in diameter. The way a P-trap protects is this: there is a water seal in the curve of the trap that stops sewer gases from backing up into your drain while allowing wastewater to pass at the same time; solids will remain in the trap so they can break down. Every time the trap is used, new water comes into the P-trap, flushing out any remnants that may be in the trap part of the pipe. However, over time, a P-trap can wear just as any other part of your plumbing system, and replacement may be necessary.

Think your P-trap may have an issue? Call Bell Plumbing and Heating today and schedule a plumbing repair appointment for your home in Denver, CO. 

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