How to Install a Sewer Trap
- 1). Loosen the nuts on each side of the P-trap's bend by hand. Note that the trap has a U-shaped section and a straight section.
- 2). Loosen the trap adapter fitted to the end of the sewer pipe coming out of the wall by turning it counterclockwise by hand. P-traps are generally smaller in diameter to sink sewer lines, so the adapter is used to attach the two different size pipes together.
- 3). Push the end of the P-trap's straight section into the center of the trap adapter. Push the end of the P-trap's U-shaped section up onto the vertical pipe running down from the sink's drain hole.
- 4). Tighten the trap adapter to the P-trap by turning the adapter clockwise by hand. Tighten the P-trap's nut surrounding the sink's vertical drain pipe and the nut on the other side of its U-shaped bend -- tighten both nuts by hand. Turn on the faucet for a few seconds to fill the P-trap's bend. Turn off the faucet.
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