GuardFlow 555-050RP Zone Valve Power Head

Upgrade your Taco 556 or 570 series zone valve with the GuardFlow 555-050RP Power Head, a precision-engineered replacement designed for seamless integration and reliable performance. This direct-fit solution replaces worn or faulty valve heads without requiring a full valve replacement, ensuring consistent heating control for both residential and commercial hydronic systems. Whether you're maintaining a multi-zone boiler setup or troubleshooting a single-zone issue, this power head delivers smooth, vibration-free operation and long-lasting durability.

The 555-050RP features a heat-actuated wax element instead of a traditional motor, eliminating noise and mechanical wear while providing precise zone control. As the wax expands with heat, it smoothly drives an internal piston to open or close the valve—guaranteeing stable, silent performance even under heavy use. Paired with a sealed piston and return spring assembly, this design ensures minimal maintenance and extended lifespan, with testing validating over 50,000 heating cycles for dependable reliability. Installation is straightforward, requiring only basic tools and a few simple steps, making it an ideal DIY-friendly upgrade for homeowners or HVAC professionals.