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Importance of a Properly Installed P-Trap

In most homes, there is a P-trap installed under bathtubs, sinks, washing machines and other household appliances that is used to drain waste water. It is a plumbing fixture that traps debris that has drained from the sink and prevents it from forming a clog deep within the plumbing system. It also stops sewer gases from passing into the home.

It gets its name because it combines two 90 degree joints with a horizontal overflow pipe which gives it the shape of the letter “P”. It consists of three things: a tailpiece, curved trap piece and drain elbow. P-traps have a water seal and this prevents poisonous sewer gases from escaping into homes. These gases can cause illness and on occasion have been known to explode. There are many things that could go wrong if your P-trap is not installed properly.

Here are a few important questions answered by the experts on issues related to P-traps:

The P-trap and outlet drain of my new sink is situated about 15 inches away from the bottom of it. Should I add piping to access the trap?

You should consider using piping to reach the trap. In case the trap is situated further down, water pressure can clear the trap of its water since waste water from the sink flows fast. When this happens, sewer gas starts emanating from the trap. If your trap is only 15” away you wouldn’t be violating the code but if it is located more than 24” away, it could become a problem and you would need to move the P-trap closer.

A P-trap was installed below my bathroom sink minus a clean-out plug. Now the sink drains very slowly. Should I change the entire elbow or install a separate clean-out plug?

In most cases, a P-trap assembly comes with compression nuts and washers that you can remove easily to clean the trap. If your fittings have all been installed with glue, it’s better to change the fittings to a style that is simple to remove and clean.

In a Shower P-Trap, Can the Lower Curvature Be Backward?
When you cement it together, the straighter side of the trap- which is not as curved- should be what the 90 degree piece is glued onto. Then the curved end should be connected to the shower drain. However, gluing the P-trap shouldn’t affect the drainage. In all probability, there is a blockage which needs to be unclogged with a snake. Also, when there is a block, the line fills with water very slowly. Your best course of action would be to determine where the block lies and try and snake it out to solve this problem.

What’s the Best Way to Clean out or Unclog a P-Trap?
Usually, drain pipes are mostly empty when waste water flows down it. However, if your toilet is draining slowly, this could indicate a blockage in the drain pipe. To remove the blockage, you might have to use a cutter head to clear your drain lines underground. Sometimes roots clog the line or it may be blocked with a collapsed part of the drain pipe. As a result of this, the water that drains from washing clothes could fill the drain and lead to slow drainage. To avoid a more serious problem like total blockage, it’s better to get a plumber to check this out immediately, possibly with the help of a camera inspection.

A P-trap is an essential part of your drainage system. If you are unsure about yours or want to learn more, put your problems in our trusted hands. Call Gillece today at (412) 831-6199!