It is possible to monitor the temperature of a source and determine if it is unable to supply the required energy; when this occurs, the source is considered degraded; when a source is in this state, it is possible to choose whether to leave it on or switch it off, but the source (or sources) that come after it in order of priority are also activated (see SOURCES PRIORITY).
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The following diagram illustrates the criteria:PHOTO TBD
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When a source is declared “degraded”, the system:
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The “degraded” status is removed when the source temperature returns to the required set point plus the hysteresis value.
Warning
If the Degradation Time parameter is set to zero, the degraded source determination function is deactivated.
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If you want to change, you have to switch off the system (or at least the request to the source), change the degradation time and then switch back on.
Note
Opentherm as a source cannot degrade, neither as DHW nor as Heating/Cooling. Only sources 1, 2, and 3 can degrade with each other and with the Opentherm source.
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