have just helped a friend remodel bathroom in basement, new shower pan, reused and reset existing toilet and vanity sink, all plumbing is hooked to a pump system
and eventually runs into town sewer lines. Shower pan is built up like old one on a 2x8 sub floor with new trap assembly to the pump system so really nothing has changed from before. Homeowner remembers this odor awhile back. Need some expertise as to where odor is coming from

thanks

Is There water in the new shower pan trap. If shower wasn't used or toilet the sewer gass is escaping through the dry trap. Same with sink. Many auxiliary fixtures hooked to sewer line is not used enough to keep water in traps it doesn't happen that often but it can happen. It sewer gas leaking out of the sewer line or where the pump system check and smell all traps in sink and shower and pump traps chase it down. Post back results

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