1. Introduction
This manual provides detailed instructions for the installation, operation, and maintenance of the TOTO TH323V104R Piston Assembly. This piston assembly is designed for use in TOTO flushometers for both 1.0 Gallons Per Flush (GPF) urinals and 3.5 GPF toilets, serving as a replacement for non-R type pistons. Please read this manual thoroughly before beginning installation to ensure proper function and safety.
2. Safety Information
Always observe the following safety precautions during installation and maintenance:
- Turn off water supply: Before starting any work, ensure the main water supply to the flushometer is completely shut off.
- Wear appropriate personal protective equipment (PPE): This may include gloves and eye protection.
- Use correct tools: Ensure you have the necessary tools for the job to prevent damage to the product or injury.
- Avoid overtightening: Do not overtighten connections, as this can damage threads or components.
- Consult a professional: If you are unsure about any step, consult a qualified plumber.
3. Package Contents
Verify that all components are present and undamaged before proceeding with installation.
- TOTO TH323V104R Piston Assembly (1 unit)


4. Installation Instructions
This section outlines the steps for replacing an existing piston assembly in a TOTO flushometer. Ensure the water supply is off before proceeding.
- Shut Off Water Supply: Locate the flushometer's control stop (angle stop) and turn it clockwise until the water supply is completely shut off. Flush the fixture to relieve any remaining pressure.
- Remove Flushometer Cover: Unscrew the cap or cover of the flushometer body. This may require a spud wrench or a large adjustable wrench.
- Extract Old Piston Assembly: Carefully lift out the old piston assembly from the flushometer body. Note its orientation for reference.
- Clean Flushometer Body: Inspect the inside of the flushometer body for any debris, mineral deposits, or worn seals. Clean as necessary to ensure a proper seal with the new piston.
- Install New Piston Assembly: Insert the new TOTO TH323V104R Piston Assembly into the flushometer body. Ensure it is seated correctly and oriented as the old one was. The piston should slide in smoothly without excessive force.
- Replace Flushometer Cover: Carefully screw the flushometer cap back onto the body. Hand-tighten first, then use a wrench to tighten securely, but do not overtighten.
- Restore Water Supply: Slowly turn the control stop counter-clockwise to restore the water supply to the flushometer. Check for any leaks around the cap.
- Test Flushometer: Activate the flushometer several times to ensure it operates correctly and that there are no leaks. Observe the flush volume and duration.
5. Operation
The TOTO TH323V104R Piston Assembly is an internal component of a flushometer. Its operation is integral to the flushometer's function. Once installed, the flushometer operates as designed:
- Pressing the flush handle or activating the sensor initiates the flush cycle.
- The piston assembly regulates the flow of water, ensuring the correct volume (1.0 GPF for urinals, 3.5 GPF for toilets) is delivered for an effective flush.
- After the flush, the piston assembly resets, allowing the flushometer to be ready for the next use.
6. Maintenance
Regular maintenance helps ensure the longevity and optimal performance of your TOTO flushometer and piston assembly.
- Periodic Inspection: Annually inspect the flushometer for signs of wear, leaks, or reduced performance.
- Cleaning: If water quality is poor or mineral deposits are common, the piston assembly may need occasional cleaning. Shut off the water, remove the piston as per installation steps, and gently clean with a soft brush and mild, non-abrasive cleaner. Rinse thoroughly before reinstallation.
- Avoid Harsh Chemicals: Do not use abrasive cleaners, solvents, or harsh chemicals on any part of the flushometer or piston assembly, as these can damage the plastic and rubber components.
7. Troubleshooting
If you experience issues with your flushometer after installing the TOTO TH323V104R Piston Assembly, refer to the common problems and solutions below:
| Problem | Possible Cause | Solution |
|---|---|---|
| Flushometer does not flush or flushes weakly. |
|
|
| Flushometer flushes continuously or runs on. |
|
|
| Water leaks from the flushometer cap. |
|
|
If problems persist after attempting these solutions, contact TOTO customer support or a qualified plumber.
8. Specifications
- Model Number: TH323V104R
- Product Type: Piston Assembly
- Compatibility: TOTO Flushometers for 1.0 GPF Urinals and 3.5 GPF Toilets (replaces non-R type)
- Material: Plastic
- Dimensions (Approximate): 3"D x 3"W x 3"H
- Item Weight (Approximate): 0.1 Pounds
- Manufacturer: TOTO
9. Warranty & Support
TOTO products are manufactured with attention to detail and a commitment to quality. For specific warranty information regarding the TH323V104R Piston Assembly, please refer to the warranty documentation included with your original flushometer or visit the official TOTO website.
For technical assistance, replacement parts, or further inquiries, please contact TOTO customer support:
- TOTO Official Website: www.totousa.com
- Customer Service: Refer to the TOTO website for current contact information (phone numbers, email, or support forms).
When contacting support, please have your product model number (TH323V104R) and purchase details available.