Objective/ Method/Outcome
Objective: Determines if the chiller is operating while pumps are inactive.
Method: Compares the chiller status signal to the pumps status signals and generates an insight when this fault occurs for greater than the defined daily threshold. Avoidable Cost and Potential Savings are determined by calculating unnecessary pump energy consumption.
Outcome: This rule generates an insight.
Description
Reference: ASHRAE Guideline 36-5.20.6.6 This rule determines if chiller is overrunning when associated primary pumps are OFF. This rule is applied for chiller. This rule is part of the CopperTree Standard rule-set.
Default Priority
High
Diagnosis
1. Inspect the equipment to see if it has been overridden manually.
2. Ensure that interfacing relays are working.
3. Verify that the status sensor is calibrated.
Message
Chiller status in ON with associated pumps OFF. Please check status sensor and equipment.
Rule Template
Insight Type: Fault Detection
Trigger Type: Active High
Notes
1. Expected values for “Pump Status” inputs are “0” or “1”.
2. Expected values for “Chiller Status” inputs are “0” or “1”.
3. The input(s) that is(are) not used should be set to “0”.
Default Values:
Const. – Threshold – Daily Hours of Faulty Operation [Hours]: 2
Const. – Cost per Hour [$]: 0
Const. – Weeks of Operation: 26
