Installation / Operation Instruction Manual

Table Of Contents
Page 33
Figure 14. Multiple Boilers, P/S Piping for Space Heating with redundant P/S for Indirect Tank
Control:
Use outdoor reset to maintain building loop temperature.
See Section 8.C.3 on page 67.
Set System pump to AUTO, pump runs during space
heating when outdoor temperature is below
warm weather shutdown.
Place jumper on T-T on Lead Boiler for constant heating call; or
interrupted if so desired.
System sensor required for cascade, outdoor reset operation
and connect to Lead boiler; place system sensor as shown,
depending on low or high temperature space heating
application.
Boiler, System and DHW pumps controlled by The Touchscreen
Control.
Pump operation congurable in pump conguration menu. See
Section 8.D.5 on page 83
Use DHW sensor, terminals 39 and 40, or aquastat, terminals
53 and 54 and connect to Lead Boiler.
During DHW operation, System pump must be OFF in low
temperature space heating applications. In high temperature
applications, System pump can continue to operate.
Caution: Boiler ring rates during DHW heating may need to
be lowered to prevent burner short cycling. Consult factory for
set-up guidance.
BMS control:
Enable/disable boiler via T-T terminals (49, 50) for space
heating.
To enable/disable boiler for DHW using an aquastat, use
terminals 53 and 54.
To enable/disable boiler for DHW using a sensor, use terminals
39 and 40.
BMS can control ring rate or setpoint via terminals 55 and 56.
(analog input).
System pump controlled by BMS or The Touchscreen Control.
NOTE: This drawing is a schematic
representation of a piping style and is
not intended to be used as a working
installation drawing. Local code
requirements must be met.
NOTE: Domestic circulator MUST be sized for
both the indirect and the boiler.