It's quite possible that if that line is not vented properly the water in
the trap could get sucked right out, from another drain in the house.

If there is no water in the trap, sewer gasses will come up.

If there is a removable trap installed on the laundry tub, when your
smelling the sewer gasses, put a towel under the trap and take the trap off,
if there is lots of water in it there is some other problem. If it's dry,
or you don't have a trap it very well could be a venting problem.

Joe

"Dave Harnish" wrote in message
...
Ray,

I wonder if the new plumbing line includes a trap?

God bless,

Dave Harnish
Dave's Repair Service
New Albany, PA
www.DavesRepair.com

570-363-2404

I'm a 32-year pro appliance technician, and love sharing what
I've learned - in a FREE Monthly Appliance Tips Newsletter.
(Back issues now posted here too!) www.DavesRepair.com

John 3:3

wrote in message
om...
We finished our basement and had extensive plumbing done in the
process, not only inside, but also outside. After our most recent
work (we had a pipe installed to evacuate our washing machine water
that was between the sheet rock and the wall -- it froze this winter.
The plumber re-installed the line on the warm side of the sheet
rock.), we notice that when we do a load of laundry, we got the odor
of sewer gas or methane eminating from our laundry tub. Any ideas
what could be causing this? -- it's very frustrating. Thanks.