Back to Back American Standard toilets..I installed back to back toilets and of course they started reverse siphoning from each other. I ordered a

[sgennaro]

.I installed back to back toilets and of course they started reverse siphoning from each other. I ordered a Totem Toilet Safety Valve, had it installed into one toilet and the siphoning stopped. However, now the floor drain in a hall closet which houses a Navien tankless water heater and water softener stinks of sewage anytime hot water is introduced, especially from the washing machine and bathtub or shower. Would a double wye resolve this sewer smell issue ??

 

[SuTester]

.I installed back to back toilets and of course they started reverse siphoning from each other. I ordered a Totem Toilet Safety Valve, had it installed into one toilet and the siphoning stopped.

I'm about to install two American Standard toilets and I just saw they are back-to-back with a straight pipe and not a "Y" style fitting. Has your Totet Toilet Safety Valve continued to work with preventing siphoning on the two toilets? Have there been any other issues?

I'm a DIY and I can open a wall and change a Case 3000 to a Glenmar Vormax, but changing a second floor in-wall "T" drain to a "Y" drain seems quite daunting to me.