Backflow Preventer ¾” Brass Dual Check Valve

The Polar Vortex Is Back - 25% OFF on all items! Don’t Risk Losing Heat   Don’t wait until the cold hits hard. Protect your heat system and stay warm with our biggest savings of the season. Stay ready. Stay warm.   Sale ends December 11 — shop now before it’s gone.   Backflow Preventer 3/4" is a required component of the Outdoor Boiler Fill Kit.  Connections are FNPT. Codes require a backflow preventer when connecting an outdoor boiler (or any external water tank) to your domestic water supply to prevent contaminants from entering (or "Backflowing") your domestic water supply. This prevents non-potable water and possibly harmful chemicals from coming out your shower head or into your pot of pasta!