TOILTOBLE THU224 Dual Flush Valve Assembly for TOTO Aquia Two-Piece Tanks ST412M

Overview

The TOILTOBLE THU224 toilet flush valve assembly is designed as a direct replacement for TOTO Aquia two-piece toilets, delivering a dependable, dual-flush option for models including Aquia II and Aquia III. It’s compatible with tanks ST412M, ST413M, ST416M, and ST464M, providing a practical upgrade path for your existing toilet setup without guesswork.

Crafted to support efficient water use without sacrificing flushing performance, this valve combines resilient materials with a precise fit. The assembly works with the original upper valve design, and, for THU224 installations, you can replace the upper component without removing the tank. This convenience can make routine maintenance smoother and faster.

Key Benefits

• Dual Flush Efficiency: Full flush at 1.6 GPF and a reduced half flush at 0.9 GPF to help conserve water while maintaining reliability.
• Durable Materials: Built from high-grade ABS plastic with reinforced silicone rubber gaskets for lasting performance and a tighter seal.
• Precise Fit for Aquia Tanks: Specifically designed to fit two-piece Aquia models, including ST412M, ST413M, ST416M, and ST464M (CST414M, CST416M, CST464MF, etc.).
• Clear Size and Height: Total height of 12 3/8 inches ensures a predictable footprint within compatible tanks.
• Installation Ease: Replace the upper valve on THU224 systems without tank removal; for THU435 and similar models, the button may require tank disassembly.

What to Expect in Real Life

Homeowners upgrading a tired flush valve often notice a quicker restore of flushing reliability and a more confident, quieter operation during everyday use. The dual-flush option supports water-saving goals without complicating the user experience. The design focuses on a clean seal and minimal maintenance over time, helping you extend valve life with proper sizing and installation.

Compatibility Notes

While this valve is designed for TOTO Aquia two-piece toilets, it may work with non-TOTO toilets if the tank height and drain opening align with the specifications. Always measure your tank and verify dimensions before purchase to avoid installation issues. Incorrect sizing can lead to flushing problems or leaks, so compatibility accuracy is a priority.

What You’ll Need to Check

• Tank height and opening dimensions match the THU224 specifications.
• Compatibility with model variants CST414M, CST416M, CST464MF or related ST-series tanks.
• Whether you’re replacing just the upper valve (THU224) or require disassembly for other models.

By focusing on real-world fit and durable materials, this valve aims to provide a reliable replacement option for Aquia owners who want a practical, non-invasive upgrade path. Always refer to the product notes and measure carefully to ensure the best outcome for your toilet.