What a TOTO Wall-Hung Toilet Actually Is
A TOTO wall-hung toilet is a bowl that hangs off a steel in-wall tank unit, with the cistern, the supply line and the WASHLET's connections all hidden behind the finished wall. Nothing meets the floor, which is why TOTO lists these as saving up to 9" of floor space compared with a standard floor-mounted toilet, and why the floor under the bowl can simply be mopped. The mounting height is adjustable from 15" to 19", so seat height is a decision you make during installation rather than one the fixture makes for you. TOTO rates the assembly to support up to 880 lbs when it is installed correctly.
Which tank you get is set by which model you buy. The AP, EP and RP bowls sold on their own use the DUOFIT WT172M in-wall tank unit. The same bowls sold as WASHLET+ sets use the WT173MA. The NEOREST WX1 and WX2 use the WT175MA. The tank itself is a one-piece blow-molded polyethylene shell, which is TOTO's answer to the obvious worry about putting a cistern somewhere you cannot see it. If you would rather keep the plumbing where you can reach it, the one-piece and two-piece TOTO ranges do the same job with an exposed tank.
The flush is TOTO's own, not a generic in-wall valve
The AP, EP and RP use DYNAMAX TORNADO FLUSH, which projects 100% of its water from the rim in a 360-degree pattern rather than feeding a ring of rim holes, at 1.28 GPF for a full flush and 0.9 GPF for a reduced one. The NEOREST WX models use TORNADO FLUSH at 1.2 GPF and 0.8 GPF. Every model in the collection is dual flush, WaterSense certified and CALGreen compliant. All of them carry CEFIONTECT, the ceramic glaze TOTO uses to keep waste from sticking to the bowl surface. You can compare the wider 1.28 GPF range if flush volume is what you are shopping on.
The problems wall-hung toilets are known for
The problems people run into with wall-hung toilets are almost all installation problems rather than fixture problems. The wall has to be framed for the tank unit before anything is tiled, so a wall-hung toilet is a remodel decision and rarely a retrofit. Wall depth matters, because the tank has to sit inside the studs. Service access is through the push plate opening rather than by lifting a tank lid. And the tank is not interchangeable with a generic one, so the model you choose commits you to the TOTO tank it was designed around.
Which TOTO Wall-Hung Toilet Is Right for You?
The right TOTO wall-hung toilet is the one whose in-wall tank suits your wall and whose seat carries the features you will use, because the four families here differ far more in the seat and the tank than in how the bowl flushes.
AP and EP: elongated and skirted
The AP and EP are both elongated front bowls with a skirted design that conceals the trapway. Both flush with DYNAMAX TORNADO FLUSH at 1.28 GPF or 0.9 GPF, both carry CEFIONTECT glaze, both are Universal Height, and as WASHLET+ sets both are built on the WT173MA in-wall tank. TOTO publishes no functional difference between them, so treat this as a choice of silhouette, not of performance. The seat is what changes: each bowl is sold with either the WASHLET S7 or the WASHLET S7A. Both cover rear, soft rear, front and wide front cleansing with a heated seat, air dryer, deodorizer, night light, EWATER+ and PREMIST. The S7A adds an auto open and close lid and a remote with an illuminated touchpad.
RP: the D-shape
The RP is TOTO's modern D-shape bowl, fully skirted, with a hole-free concave rim and what TOTO describes as a gentle wave-line with elegant detailing on the sides. It flushes at the same 1.28 GPF and 0.9 GPF and sits on the WT173MA tank as a WASHLET+ set. Its two seats differ more than the S7 pair do. The RW gives you front and rear washing with adjustable temperature and pressure, a heated seat, automatic deodorizer, PREMIST, two-user memory, auto flush and auto open and close. The RX keeps the washing, heated seat, deodorizer and two-user memory, but TOTO lists no auto flush and no auto open and close on it. Neither RP seat lists an air dryer, so if a dryer matters, the S7 pair on the AP and EP is where to look. The RP's base color is Cotton, with Matte Black and Matte White made to order.
NEOREST WX1 and WX2: one integrated fixture
The NEOREST WX models are not a bowl with a seat fitted to it. Bowl and top unit are designed as a single fixture, they flush with TORNADO FLUSH at 1.2 GPF or 0.8 GPF, and they run on the WT175MA tank rather than the WT173MA. Both list an instantaneous water heater for continuous warm water, a dual-action spray that oscillates and pulsates, a warm air dryer with five temperature settings, EWATER+ that auto-cleans the wand, bowl and under-seat after every use, four-user memory, and auto flush with a manual backup for power outages. Both are ADA compliant. The WX2 adds ACTILIGHT CLEAN LIGHT technology built into the lid. The rest of the range sits in TOTO NEOREST.
What TOTO wall-hung installation involves
Installing a TOTO wall-hung toilet means opening the wall and setting the tank unit into the framing before the bowl goes on. TOTO specifies commercial 2" x 6" studs, with an optional residential installation using 2" x 4" studs, and the tank unit carries a 2" x 6" polyethylene outlet. You set the mounting height anywhere from 15" to 19" while the frame is open, which is the one chance you get to place the seat where you want it. On a WASHLET+ set the electrical supply is run inside the wall at the same time, so no water or power line shows on the outside of the fixture. This is plumber work, not a seat swap.