Friday, September 30, 2011

Stop Unwanted Heat w/ Flow-Checks

Flow-Check valves prevent unwanted heat in closed-loop hydronic heating systems. In a single zone system, hot water can flow from the boiler at low rates even when there is no call for heat. If nothing stops the water’s path, the heated space may become unnecessarily warm. The same situation can arise in systems with multiple zones that are zoned by circulators rather than zone valves. Unchecked, heat can be thermosiphoned around the loop or into zones that are not calling for heat.

A flow-check valve installed close to the circulator(s) solves this problem. It’s a simple mechanical device that completely blocks flow in one direction and prevents flow in both directions when system pumps are not powered. Visit for flow-check valves from Taco and Bell & Gossett.