3/4" Horizontal Hydronic Flo-Chek Valve.

Taco 218-3 Cast Iron Hydronic Flo-Chek Valve – Professional Technical Information

The Taco 218-3 Cast Iron Flo-Chek Valve is designed for precise hydronic flow control in hot water heating systems. Built to prevent unwanted gravity circulation, this valve allows system stability and efficiency by restricting flow when a heating zone is inactive. Constructed from high-grade cast iron with a reliable automatic actuator and manual bypass feature, the 218-3 ensures dependable performance across a wide range of operating temperatures and pressures. Ideal for use in both residential and light commercial hydronic applications, it supports consistent system operation and simplifies zone management.

Technical Specifications

• Manufacturer: Taco Comfort Solutions
• Model Number: 218-3
• Product Type: Hydronic Flo-Chek Valve
• Configuration: Universal – Angle/Straight
• Nominal Size: 3/4 inch
• Connection Type: NPT Female Threaded
• Body Material: Cast Iron
• Actuation Type: Automatic with Manual Thumb-Screw Bypass
• Medium: Hot Water or Water/Glycol Solutions
• Mounting Orientation: Horizontal Installation
• Maximum Operating Pressure: 125 PSI (862 kPa)
• Maximum Operating Temperature: 277°F (136°C)
• Flow Direction: Indicated by cast arrow on body
• Dimensions: 3-29/32 inch Width x 4-29/32 inch Height
• Seal Material: High-Temperature Elastomer
• System Compatibility: Forced Hot Water and Multi-Zone Hydronic Systems
• Manual Override: Thumb screw for gravity feed operation in case of pump failure
• Finish: Industrial-grade corrosion-resistant coating
• Serviceability: Field-replaceable internal components

Performance and Application Features

• Prevents gravity circulation in hydronic systems when the heating zone is inactive.
• Allows hot water boilers to operate continuously for domestic water use without heating inactive zones.
• Automatic actuator provides reliable flow control without external power or adjustment.
• Manual bypass screw enables gravity circulation for emergency operation or maintenance.
• Cast iron construction ensures strength, durability, and thermal stability under high temperatures.
• Compact design allows easy installation in horizontal piping configurations.
• Compatible with both water and glycol mixtures, supporting freeze-protection applications.
• Reduces energy loss and improves system efficiency by maintaining proper zone isolation.
• Designed for continuous service in residential and light commercial hydronic heating systems.
• Minimal maintenance required, with accessible design for service and inspection.

Professional Summary

The Taco 218-3 Cast Iron Hydronic Flo-Chek Valve provides contractors with a dependable solution for maintaining controlled circulation within hydronic heating systems. Engineered for precision and durability, it automatically prevents unwanted flow while allowing for manual operation when needed. With a robust cast iron body, high-temperature sealing materials, and compatibility with glycol-based fluids, the 218-3 offers long-term reliability and stable operation under demanding conditions. Designed for professional installation in multi-zone systems, this valve supports efficient performance, operational safety, and extended service life across a broad range of hydronic applications.