Lead Lag Instructions - NTI Trinity Tft399 Installation And Operation Manual

│Installation and Operation Instructions
Trinity

11.0 LEAD LAG INSTRUCTIONS

Multiple Boiler Applications
The Tft controller has the internal capacity to stage or Lead-Lag up to 8 boilers configured in a cascade. This
Lead-Lag capability allows a designated "Master" boiler to communicate with and effectively control each
boiler in a multiple boiler system. This function is accomplished by "Daisy Chaining" a 3-wire cable between
each of the boilers and enabling the Master parameter in the boiler of your choice. The boiler with the Master
parameter enabled becomes the single point of contact for Central Heating, Domestic Hot Water and Outdoor
Reset settings and control wiring. Use the instructions detailed in this section to set-up and install the cascade
boiler system; reference Appendix A – Controller and Touchscreen Display Instructions for details on more
advanced settings and for assistance with navigating the touchscreen display.
Figure 11-1 illustrates the basic plumbing requirements for a three Trinity Tft boilers
installed in cascade. Refer to Figures 10-1 through 10-3 for identification of boiler
water connections, as their locations will vary between boiler models.
50
Figure 11-1 Multiple Boiler Cascade – Plumbing Configuration
Tft399 Models Illustrated
Tft Series