Hi, Newbie homeowner here with a smell issue in a bathroom. The bath in question has a tub/shower, toilet and double sink. The bath is on the main floor of a ranch. The basement is finished with a full bath with an ejector pump.
The smell isn't there all the time so I'm thinking one or all of the trap water is somehow being pulled out of the traps allowing the smell to come up.
My question is if the backflow value on the ejector pump isn't working correctly, could this be the culprit? Could the backflow be pulling the water out of the traps? Anyone have any ideas?