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HTD
C O N F I G U R AT I O N
8.D.4.d Redundancy
To navigate to the Cascade Redundancy Screen, touch the Cascade Icon on the Configuration Screen, then touch the
Redundancy Icon on the Cascade Configuration Screen.
The Cascade Redundancy Screen allows the selection of one of three options for redundancy in cascade systems.
These options are:
• Boiler Internal Set Point
– In a cascade configuration, upon loss of communication with the lead unit, the lag units
will continue to operate in the same manner as when the communication stopped. For example, if a lag unit was firing
to satisfy a cascade heat demand, it will continue to satisfy the heat demand upon loss of communication with the
Leader.
• Redundant Lead
– In a cascade configuration, upon loss of communication with the lead unit, a second unit will
assume lead responsibilities.
• Disable Redundancy
– In a cascade configuration, upon loss of communication with the lead unit, lag units will no
longer satisfy the cascade heat demand.
8.D.5 Hybrid
To navigate to the Hybrid Configuration Screen, touch the Hybrid Icon on the Configuration Screen.
The Hybrid Configuration Screen allows adjustment of the following parameters:
• Hybrid Enable –
This parameter allows Hybrid Mode to be enabled or disabled.
• Lag Mode –
This parameter allows Lag Mode to be enabled or disabled.
• Hybrid Set Point –
Based on the system return temperature, with Hybrid Mode enabled, this temperature set point
determines which type of boiler (condensing or non-condensing) runs first to satisfy a heat demand.
•HybridDifferential–
This parameter is a +/- offset of the Hybrid Set Point used to prevent condensing in non-
condensing units.
• Hybrid Delay –
This parameter is a time delay that, in addition to Hybrid Differential, is used to prevent condensing
in non-condensing units.
