HydroTherm: Modulating Lead/Lag Boiler Controller
July 24, 2006
The Mod-Smart is a condensing boiler modulating lead/lag controller designed to maximize the performance and efficiency of multiple boilers with maximum flexibility. It modulates the entire system at the lowest possible firing rate that will satisfy the overall plant heating load. The controller monitors outdoor air temperature, resetting the boiler water temperature set point. The control system allows for the full modulation of up to 10 boilers at the same firing rate, bringing lag boilers up to a predetermined ramp rate to meet the heating load with minimum overshoot. PID controls automatically adjust boiler rates to suit the overall plant hot water. Optional features of the control system include reverse/return piping systems, primary/secondary piping systems, header pump sequencing, and/or smart boiler sequencing.
HydroTherm, 260 North Elm St., Westfield, MA 01085; 413-564-5515; www.hydrotherm.com