Great Washer Drain Vent
If the washing machine drain continues to have backflow problems ensure the drain vent is connected and properly working.
Washer drain vent. There is also what I think is an AAV vent at the top. A vent that comes before a trap may not be helpful. If they omit the trap.
In each A is the vent B is the trap arm and C is the drain. The 90 in the corner should be a long sweep. To be confident that no siphoning of water will take place the drain plumbing should be a minimum of 30 high.
Drain piping can be horizontal 14 per foot vertical or 450- vent piping shall be free of sags and be graded and connected to drip back by gravity to drain pipe it serves. All plumbing fixturesincluding washing machines must be vented. Jan 14 2019 - how to plumb drain line for washer and vent with studor vent - Google Search.
In-Line Vents on washer drain. The AAV wont help the sink there with the washer dumping over the sink trap arm. Prevent sewer gases from escaping into your home.
Depending on the distance between the drain pipes for the shower and washing machine you may be able to install a single vent at the drain further downstream to serve them both. In order for the drain hose to function properly the drain must be at least 30 from the floor and less than 8 feet high. The washer should have come in below the sink.
Properly vented drains allow the P-trap to do its job. For a 2-inch drain line this distance is usually 5 feet. Improperly vented drains can be sluggish and noisy and can emit hazardous fumes.