The Hydro-Flow™ Model 3100 retractable insertion vortex flowmeter is designed for measuring hot water, chiller water, and condensate flows. Design features include no moving parts and limited maintenance requirements. The Model 311 offers a turndown ratio of 30:1, and measures flows as low as 0.5 ft/s, or 0.15 m/s. It is available for line sizes 3 to 20 in. with either a thread-o-let or saddle mountings. A choice is available between frequency pulse or 4-20 mA current output.