View Full Version : Disposal causes kitchen sink to back up

09-12-2005, 07:20 PM
I have a problem with my kitchen sink. When I use my disposal the sink backs up and water will not drain. I have had a plumber look at it, he snaked the line and found no blockages. He thought it was a venting problem, so 287.00 later he installed a vent pipe under the sink. This worked for 2 days, but today we used the disposal to get rid of some fish (no bones) and the sink backed up. The only way to get the water to drain is to plug the other side of the sink and run the disposal until the water starts to drain. No other drain in the house is affected. There is no food stuck in the disposal or trap when the water backs up. What could be causing this?

Dunbar Plumbing
09-12-2005, 08:06 PM
Sounds like ineffective drain cleaning on the part of the plumber, but the type of piping might of been the culprit. What type of piping do you have serving as drains? If galvanized then I can see why it is clogging right back up; I've removed piping I have drain cleaned and it looks like it drilled a hole through the clog, nothing else but a small pathway.

09-12-2005, 08:16 PM
All Pipes are PVC. This only happens when we use the disposal it does not matter how little or how much food we put down it. The plumber has snaked the drain, but do you think it needs to be done again? I have snaked the drain myself and nothing ever comes back on the end of the snake.

09-12-2005, 08:22 PM
If the drain is plugged, which is a good possibility, then the device he installed will not allow the sink to drain, assuming it was even needed, which is not likely. We cannot tell you exactly what the problem is, but a proper snaking will not stop up again in a matter of days.

09-12-2005, 09:02 PM
Thanks for the advice. I will have the plumber come back to Re-snake the drain pipe. Would a camera on the end of the snake be a good idea to ask for? This may reveal the real problem.

Dunbar Plumbing
09-12-2005, 09:04 PM
Only if the line is 3" or larger. More than likely a kitchen drain is 1.5" or 2". The camera would not be able to get past the first turn in a pipe that small.

09-12-2005, 09:07 PM
Got it. Thanks again for the advice so late at night, good thing Monday Night Football is on.

09-13-2005, 05:24 AM
HJ"s right.........I've found that the best way to clean a drain like you describe is to set it up so you can have a continuous flow of water while running the snake. You should have room to cut in a wye or tee and put a c.o. plug in it and get the fitting 3 or 4" above the trap.
Use a good sturdy snake. Put a kink on the lead end and you can do a very good job on pvc, galv or copper.
Being able to flush while snaking is the key.
Of course the longer the drain, then the more often it needs cleaning.
Another variable is how the disposal is used...

p s It will make it such an easy job for the next time..