Originally Posted By: ecrofutt
This post was automatically imported from our archived forum.
Joe’s advice sounds okay if the drain isn’t draining. I prefer mechanical drain cleaning rather than chemical, but that’s just a choice thing. You could also get a bulb that attaches to the end of the hose, expands when you turn on the water and keeps the hose in place and water from coming back up. The grass and cat hair would contribute to clogging the drain and stopping water from leaving the shower. Not really applicable to your situation.
With the problem being the trap not holding water to prevent the sewer gases from backing thru the trap, it's more likely you have a problem in your vent. That would allow the water to be sucked out of the trap.
I'd focus on the vent issue. Maybe run the same hose, with the bulb on it, down the vent stack and try to blow it out.
There are other ways by which a trap can lose its water seal. One is self- siphonage; a natural phenomena which sucks that water out of the trap because the fixture is not properly vented. You’ll recognize this plumbing ailment by the loud “swoosh” which accompanies the departure of the water. Another trap-drainer is called assisted-siphonage, resulting from suction built up when the water from another waste pipe flows too close to the fixture trap. Both are problems for your licensed Plumbing Contractor
You mentioned you have to remove the washing machine to get to the access. Is your washing machine running when this happens. That could contribute to the "assisted-siphonage" thing.
B4U Close Home Inspections