Dcommoncents
New Member
Hi, first time poster. Thanks in advance for any help.
I am installing a Toto wall mounted toilet with an in-wall tank system. The system comes with a 90 degree outlet pipe that sits in the bracket. Ideally, I would like to run the outlet pipe horizontally out of the carrier in order to avoid framing difficulties (i.e. floor joists). As I hope the pictures I will (attempt to) post show, the horizontal waste line from the old toilet flange runs under the floor just to the left of the wall mount toilet before teeing into the main stack. It is that horizontal run that I need to connect the wall mount toilet to.
My concern is that, I have not seen these toilets installed with the outlet pipe mounted with an initial slope of less than 45 degrees, and usually they run vertically. Is there any reason why running the outlet pipe horizontally with a 1/4 inch per foot slope would be problematic? I contacted Toto customer service, and they said that a horizontal mounting will cause siphoning of water out of the toilet, but they couldn't explain why, and that makes no sense to me based upon the appearance of the outlet pipe and my admittedly limited knowledge of plumbing theory.
I am installing a Toto wall mounted toilet with an in-wall tank system. The system comes with a 90 degree outlet pipe that sits in the bracket. Ideally, I would like to run the outlet pipe horizontally out of the carrier in order to avoid framing difficulties (i.e. floor joists). As I hope the pictures I will (attempt to) post show, the horizontal waste line from the old toilet flange runs under the floor just to the left of the wall mount toilet before teeing into the main stack. It is that horizontal run that I need to connect the wall mount toilet to.
My concern is that, I have not seen these toilets installed with the outlet pipe mounted with an initial slope of less than 45 degrees, and usually they run vertically. Is there any reason why running the outlet pipe horizontally with a 1/4 inch per foot slope would be problematic? I contacted Toto customer service, and they said that a horizontal mounting will cause siphoning of water out of the toilet, but they couldn't explain why, and that makes no sense to me based upon the appearance of the outlet pipe and my admittedly limited knowledge of plumbing theory.
Last edited by a moderator: