Q:My client has a sewer ejection tank in his basement for a laundry and a half-bath. When the washer drains and the tank pumps out, the liquid overwhelms the vent's ability to supply enough makeup air, causing a "pull" on nearby traps (mainly the first-floor toilet). What is the proper way to vent this system, and can I add venting to remedy this situation?
A: Mike Casey, a licensed plumbing contractor and ICC Certified Combination Inspector in San Diego responds: Clothes washers pump out a lot of water quickly, which can put a load on the sewage ejector pump. But that shouldn't affect the traps connected to the sewage ejector tank if it's properly vented.
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