Objective/ Method/Outcome
Objective: Determines if effective temperature setpoint remains unchanged when occupancy schedule changes.
Method: Compares the changes in occupancy schedule to the changes in effective temperature setpoint. If the effective temperature setpoint remains unchanged when the occupancy schedule changes, the hours of faulty operation are calculated.
Outcome: This rule generates an insight if the Weekly Hours of Faulty Operation exceeds the acceptable weekly threshold.
Description
Reference: ASHRAE90.1-6.4.3.3.2
This rule determines if effective heating temperature setpoint is unchanged between occupied and unoccupied schedule. An insight will be generated if occupied effective cooling temperature setpoint does not change during unoccupancy by the specified deadband.
This rule is part of the CopperTree Standard rule-set. (Aliased Celsius / Aliased Fahrenheit)
Default Priority
Medium
Diagnosis
1. Verify if active setpoint resets based on building schedule.
2. Verify if unoccupied setpoint value is correct.
Message
Unoccupied setback control might be missing.
Rule Template
Insight Type: Fault Detection
Trigger Type: Active High
Notes
1. Expected values for “Occupancy” inputs are “0” or “1”.
Default Values:
Const. – Acceptable Weekly Hours of Faulty Operation [Hours]: 8
CTLs:
Cooling SP Unchanged When Unoccupied – Hours of Faulty Operation (CUSUM) Cooling SP Unchanged When Unoccupied – Weekly Hours of Faulty Operation
