926743-00

Condensing and Non-Condensing Outdoor Reset Modulating Boiler Control Overview: The Mini-MOD-CNC is an outdoor reset multiple boiler heating control. It operates two different groups of boilers, condensing and non-condensing. It operates both modulating and multi-stage boilers. It changes the lead boiler group to condensing when the system target temperature is below a specified switching set point. However, when the system target temperature rises above the switching set point, the Mini-MOD-CNC will switch the lead boiler group to the non-condensing. This design evolved from heating applications need to increase their operating efficiencies while reducing their equipment initial investment. System Target Temperature Switching of Lead Group:  The Mini-MOD-CNC uses a target switching set point with an adjustable switching delay. If the target temperature was below the switching set point, the Mini-MOD-CNC will use the condensing boiler group as the lead boiler group. If the target temperature rises above the switching set point for a specified delay period, the Mini-MOD-CNC will switch the lead boiler group from the condensing to the non-condensing lead boiler group. Parallel or Normal Modulation:  For the modulating group of boilers (condensing or non-condensing), an advanced PID logic has been used to provide an efficient, smooth, and adjustable modulation that can fit most applications whether the boilers are to sequence normally, one after the other, or in parallel. With numerous configurable parameters like Ignition %, Modulation Start %, Gain, Lag Delay, Soft-Off , and Last Stage Hold, the PID logic can be adjusted to meet any building specific heating application. Domestic Hot Water Control with Optional Priority  It can be configured with Domestic Hot Water call option. It will increase system water temperature when Domestic Hot Water is needed. In addition, it allows for optional priority of the domestic hot water over heating.