Lochinvar Sync Condensing Boiler 1.3 - Manual (Page 25)

1
Service
(continued)
25
Cascade Parameters Screen:
Cascade Operation
When multiple boilers are installed, they can be wired
together in a cascade sequence. A maximum of eight (8)
boilers can be controlled from a single control. In this
application one boiler would be designated as the Leader and
all others would be designated as Members. The designated
Leader boiler determines the total output needed from the
group based on the set point and the system sensor reading.
Reference the Wiring of the Cascade section in the SYNC
Installation and Operation Manual for more information
regarding the cascade feature.
The Cascade Screen allows access to four (4) parameters.
Those parameters are as follows:
• Cascade Address - The boiler designated as the Leader
should be programmed with address 0-1. All Member
boilers require addresses from 2-3 through 14-15. The
address must be different for each member. The
addresses can be in any order, regardless of the order in
which the boilers are wired together. This parameter can
only be changed by the installer. The default address is
0-1.
• Cascade Off Differential - Sets how many degrees above
set point the temperature has to go before the lead boiler
will shut off. This parameter can only be changed by the
installer. The temperature range of this parameter is 0° to
72°F. The default value is 10°F.
• Cascade Off/On Differential - Sets how many degrees
below the turn off temperature (set point + Cascade Off
Differential) the temperature has to go before the lead
boiler will turn on. This parameter can only be changed
by the installer. The temperature range of this parameter
is 0° to 72°F. The default value is 20°F.
• Maximum Outlet Temperature - Sets the set point that
individual boilers will attempt to achieve in a cascade.
When a boiler is commanded to fire by the Leader, it will
attempt to achieve this temperature at its outlet. The Leader
will control the modulation of the last boiler to fire in order
to hold the temperature at the system supply sensor to the
user set point. If any of the boiler outlet temperatures reach
the Maximum Outlet Temperature setting, the boiler will
then modulate down on its own in order to keep its outlet
temperature within the Maximum Outlet Temperature
setting. Therefore, this parameter can be used to limit the
outlet temperatures of all the boilers in a cascade.
Note that this parameter does not apply when the boiler is
in Hot Water Generation Mode. This parameter can be
changed by the user or the installer. The temperature range
of this parameter is 32° to 212°F. The default value is 185°F.
Reference page 18 for information regarding changing
parameters.
Time - The time is displayed in the upper right-hand corner of
the display. It is displayed in 24 hour format. Reference the
night setback parameters on page 24 for information regarding
adjusting the date and time.
Back button - Pressing this button will back the screen up to the
previous screen.
Service Manual