Is it a bad idea to have the P trap pipe extend deep into the sewer pipe?

Old 02-04-19, 08:39 PM
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Question Is it a bad idea to have the P trap pipe extend deep into the sewer pipe?

I am redoing the piping under the kitchen sink. The P trap horizontal pipe 1.5in extends about 3 to 4 inches into the horizontal sewer ABS 2in pipe. Should I trim the P trap pipe to be closer to where the two meet? Or is it better to keep it long?

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Last edited by PJmax; 02-05-19 at 01:12 AM. Reason: added pic from link
Old 02-05-19, 01:13 AM
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That's fine. No need to cut it.
Old 02-05-19, 05:05 AM
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I agree, as long as it fits there is no need to cut it shorter.
Old 02-12-19, 10:29 AM
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The only caveat is if there's a bend in the pipe in the wall. Most drain pipes will only be 2-3" into the wall, then drop into a sanitary tee or an elbow. If the slip fitting goes into the bend/elbow too far, it can cause clogs (since there's only 1/2" or 1" actual clearance).

If it's the way it is in your drawing, no issue.

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