Can Toto Ultramax II be mounted back to back in older home?

[Macawmom]

I have read so many excellent reviews here of the Ultramax II and its great flush ability. I am planning a restyling of my 1969 tiny master bathroom. Keeping the 30" shower as is and replacing the original blue Formica vanity and blue toilet. The problem is this toilet is back to back with the old mocha colored toilet in the much larger guest bathroom. I would ideally like to replace both of these with the Ultramax II but the installation instructions said:
"Due to the powerful performance of our Cyclone, G-Max, E-Max and Power Gravity flushing systems, they are not specified for back-to-back installations. The only means of installing these toilets in a back-to-back situation is when the toilet drain connections incorporate a WYE fitting. Please contact your builder or contractor prior to this installation. "
Do I really need to have someone tear up my floors to find out if I have a WYE fitting or a
Double Sanitary Tee / Sanitary Cross, which it says can not be used?
These bathrooms are on the second floor, if that makes any difference.
Is there a different toilet that would have a cyclonic flush that would work better for my situation?

I replaced the first floor toilet with the American Standard Cadet 3 a few years ago but I do not like the flush action on it at all. We also get lots of calcium buildup on our toilets.

 

[Terry]

If you have a Cadet 3 and things are working fine, then you should be okay with the TOTO also. Both use a 3" flush valve in the tank.
I do like the Ultramax better.

 

[Sponsor]

 

[Macawmom]

If you have a Cadet 3 and things are working fine, then you should be okay with the TOTO also. Both use a 3" flush valve in the tank.
I do like the Ultramax better.

Thanks, Terry. The Cadet 3 is on the first floor. The two toilets I want to replace are on the second floor. Does that make a difference?

Thanks for your reply.

 

[Jadnashua]

Thanks, Terry. The Cadet 3 is on the first floor. The two toilets I want to replace are on the second floor. Does that make a difference?

Thanks for your reply.

Yes...unless the fitting behind the two toilets is the proper one...flushing one will tend to push stuff into the other one, and it won't work well. Older toilets using more water, tended to drain fairly slowly. To get a decent flush with the new, low-flow ones, they must move the water and waste quite fast, and unless the fitting directs things down verses just into with little restriction, it will just jet into the other toilet. This is true for most ANY new, low-flow toilet...Toto is not the only one that will have issues, but they may be one of the minority that warn you in advance.

 

[Macawmom]

Thanks, so how would I know which type of fitting is installed in my pipes?
Or should I just assume in a 50-year-old house that it's not the WYE type of fitting?
Thank you for your responses on a holiday weekend.

 

[WJcandee]

Any decent modern toilet is going to have the same potential issue that Toto highlights in its instructions. That is, mounted back to back across a double San-T, there is the possibility that the more-aggressive flushing action could siphon the other toilet a little or shoot some stuff across the T and cause some sloshing in the bowl of the other toilet.

You have no way of knowing what fitting is in there without opening the wall/ceiling/floor (except maybe, just maybe, with a boroscope), but, more importantly, you really don't have any way of knowing whether there will be a problem and if so how much of one until you try it, which is the cheapest and most-definitive route. You could go through all the effort of examining what you have and you still wouldn't know for sure whether you would end up with a problem. We have posts on here from folks describing symptoms where the likely culprit is the fitting setup between two back-to-back toilets, and we have posts on here where people have mounted them no problem.

One obvious point is that just because the toilets seem to be more-or-less in the same place on either side of a wall doesn't mean that they are installed back-to-back. They could be independently-connected to the drain line at different spots, for example. I'm not saying that that's likely, but it's also not impossible.

One other thing to mention is that I have always viewed those Toto instructions as a bit of a cop-out and butt-coverer. The reality is that virtually nobody would install the fitting they "require" in old (or even new) construction because the space required for their recommended setup is significantly-greater than the typical fittings used even today; very few architects/contractors would adjust things to provide the necessary space for the Toto-recommended fittings, and it would normally be a significant challenge to do, if not impossible, as a retrofit. I think that Terry and HJ recommend a double-fixture fitting, which isn't going to completely-eliminate the possibility of a problem, but in many cases will work acceptably.

Picking a different toilet isn't likely to change things, because any toilet that actually functions on 1.6gpf or less is going to have a more-aggressive flush than the drain-the-swimming-pool toilets of old.

Me, if I wanted to replace the toilets, I would get the toilets I want, install them, and deal with the issues if and when they arise.

 

[Terry]

I think that Terry and HJ recommend a double-fixture fitting, which isn't going to completely-eliminate the possibility of a problem, but in many cases will work acceptably.

Even the double fixture fitting allows water to skip across and push a bit of water out of the opposing bowl. It's not that big a deal though if both bowls are used somewhat equally. There will always be some water to maintain a seal in the bowl that has the lowest water.
Replacing the toilets with the Ultramax is still a good idea.

 

[Macawmom]

Even the double fixture fitting allows water to skip across and push a bit of water out of the opposing bowl. It's not that big a deal though if both bowls are used somewhat equally. There will always be some water to maintain a seal in the bowl that has the lowest water.
Replacing the toilets with the Ultramax is still a good idea.

Thank you again for all of your help.

Any decent modern toilet is going to have the same potential issue that Toto highlights in its instructions. That is, mounted back to back across a double San-T, there is the possibility that the more-aggressive flushing action could siphon the other toilet a little or shoot some stuff across the T and cause some sloshing in the bowl of the other toilet.

You have no way of knowing what fitting is in there without opening the wall/ceiling/floor (except maybe, just maybe, with a boroscope), but, more importantly, you really don't have any way of knowing whether there will be a problem and if so how much of one until you try it, which is the cheapest and most-definitive route. You could go through all the effort of examining what you have and you still wouldn't know for sure whether you would end up with a problem. We have posts on here from folks describing symptoms where the likely culprit is the fitting setup between two back-to-back toilets, and we have posts on here where people have mounted them no problem.

One obvious point is that just because the toilets seem to be more-or-less in the same place on either side of a wall doesn't mean that they are installed back-to-back. They could be independently-connected to the drain line at different spots, for example. I'm not saying that that's likely, but it's also not impossible.

One other thing to mention is that I have always viewed those Toto instructions as a bit of a cop-out and butt-coverer. The reality is that virtually nobody would install the fitting they "require" in old (or even new) construction because the space required for their recommended setup is significantly-greater than the typical fittings used even today; very few architects/contractors would adjust things to provide the necessary space for the Toto-recommended fittings, and it would normally be a significant challenge to do, if not impossible, as a retrofit. I think that Terry and HJ recommend a double-fixture fitting, which isn't going to completely-eliminate the possibility of a problem, but in many cases will work acceptably.

Picking a different toilet isn't likely to change things, because any toilet that actually functions on 1.6gpf or less is going to have a more-aggressive flush than the drain-the-swimming-pool toilets of old.

Me, if I wanted to replace the toilets, I would get the toilets I want, install them, and deal with the issues if and when they arise.[/QUOTE

Thank you for explaining this so thoroughly. I can live with a little sloshing, if need be.
Going to install the Ultramax II and not look back.