NTI Trinity Tft399 Installation And Operation Manual page 52

│Installation and Operation Instructions
Trinity
Lead Lag Instructions – Central Heating
Central Heat Demand Switch (Room Thermostat) – connect to R (24VAC) and CH2 (LL) of the Master
Boiler; see Field Wiring Table 12-2b and Figure 12-2. Switch must be an isolated end switch (dry contact).
Central Heat Setpoint – at the Master boiler only, set the CH setpoint via the Lead Lag Master Configuration
menu, accessed as follows:
Configure – Lead Lag Master Configuration – CH setpoint
Outdoor Reset Settings – at the Master boiler only, set the Outdoor reset parameters via the Lead Lag Master
Configuration menu, accessed as follows:
Configure – Lead Lag Master Configuration – Advanced Settings – Outdoor reset
CH Pump – one boiler in the cascade can be chosen to operate the Central Heating pump via its PUMP C
output; see Field Wiring Figure 12-1 and Table 12-1. From the respective boiler display, check the box next
to Use for Lead Lag Master demands for the CH Pump to ensure proper pump behavior. Menu access to the
CH Pump parameters is as follows:
Configure – Pump Configuration – Central Heat pump – Use for Lead Lag Master demands
Lead Lag Instructions – Domestic Hot Water
Tank Thermostat – connect to SENSOR COM and DHW of the Master Boiler; see Field Wiring Table 12-2a
and Figure 12-2. Switch must be an isolated end switch (dry contact).
DHW Setpoint – at the Master boiler only, set the DHW setpoint via the Lead Lag Master Configuration menu,
accessed as follows:
Configure – Lead Lag Master Configuration – DHW setpoint
DHW switch (Lead Lag) – at the Master boiler only, set DHW switch equal to DHW (S6) sensor shorted via the
Lead Lag Master Configuration menu, accessed as follows:
Configure – Lead Lag Master Configuration – Advanced Settings – Domestic Hot Water – DHW switch
DHW enable (Local) – at the Master boiler only, set DHW enable equal to Disabled via the Domestic Hot
Water Configuration menu, accessed as follows:
Configure – Domestic Hot Water Configuration – DHW enable
DHW Pump – one boiler in the cascade can be chosen to operate the DHW pump via its PUMP A output; see
Field Wiring Table 12-2b and Figure 12-2. From the respective boiler display, check the box next to Use for
Lead Lag Master demands for the DHW Pump to ensure proper pump behavior. Menu access to the DHW
Pump parameters is as follows:
Configure – Pump Configuration – DHW pump – Use for Lead Lag Master demands
Tank Sensor – when operating in a cascade system, the boiler controls do not support the
use of a tank sensor; a tank thermostat (switch) must be used.
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Tft Series