We have a shower in our basement and the drain is run through a 2″ copper pipe for about 25′ to the floor drain in our laundry room. The copper pipe just sticks down into the floor drain about 1-2″. When we take the first shower we get a sewer smell in the shower and it sometimes spreads through the basement. We had the Roto Rooter people come in and run a drain cleaner through the copper pipe. It did not clear up the problem. The smell still exist. There is water in the floor drain that is visible if you mowe the copper pipe out of the way of the drain. What could be causing the smell to come up through the shower? Would there be a problem with the floor drain elbow?
You said you ran the pipe 25 feet BUT you didn’t mention the trap for the shower or how far away is the vent from the trap?
Instead of calling a rooter guy WHY not call a Licensed Master plumber as NO ONE knows more about “Proper” venting or drainage than a plumber.
What you did describe sounds like a HIGHLY ILLEGAL indirect waste hook up. Any 1st year apprentice would also know SNAKING does not remove odors AND chemicals most of the time cover up the smell by adding another type of smell.
Call a REAL Licensed plumber and ask them about water jetting the pipes clean to a like new condition removing all the old soap scum build up that causes bacteria that in turn causes the smells. Call the RR guy and ask for your money back. Good luck