installing toto carlyle, need help!!!

[Toto trouble]

Received Toto carlyle toilet that I bought online. After reading instructions I see that the toilet is not specified for back to back installations, unless you have a double combination WYE. I have a 4" cast iron double sanitary tee. Does this mean I have to send back this toilet? There is a wet wall separating the toilets, thus increasing the distance between the toilets, does this help? Its Sunday so Toto customer support not available and I was hoping to install it today.

 

[Terry]

We do it all the time. Most homes have a back to back fixture cross.
It works, but can displace a little water in the opposing bowl. But then any of the new high performance toilets will do the same.
I would go ahead and install it. I did on mine and others.

 

[Sponsor]

 

[Toto trouble]

I was hoping that was the case. Thank you very much for the info. Now to work.

 

[Basement_Lurker]

Double san tees should never be used except in a venting application. If you install that toilet, some of the water/waste could jump across to the other toilet's trap arm. However, I should say, that if you really do have a 4" san tee with 4" trap arms going to each toilet, you should be alright. Most likely the trap arms are very short, being that it is a back to back installation, so the grey water won't accumulate a lot of speed, and the 4" fitting will definitely decrease the chance of water skipping over it compared to a 3" fitting.

However, the instructions do say you should have a double wye (or a double fixture fitting would work as well), so that pretty much says it all.