Hot Water System – Pump is operating with boilers OFF
Objective/ Method/Outcome
Objective: Determine if the pump is operating while the boiler is inactive.
Method: Compares the pump operation to boiler operation and generates an insight when a mismatch occurs for greater than the defined daily threshold. Avoidable Cost and Potential Savings are determined by calculating the unnecessary pump energy consumption.
Outcome: This rule generates an insight.
Description
Reference: ASHRAE Guideline 36-5.21.6.3 This rule determines if pump is overrunning when boilers are OFF. This rule is applied for pump. 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
The hot water pump is running out of sync with the Boiler Sequence. Please investigate the sequence of the Hot Water System.
Rule Template
Insight Type: Fault Detection
Trigger Type: Active High
Inputs
| Input | Unit | Tags | Description |
|---|---|---|---|
| Hot Water Pump Status | Hot Water Pump Status, Hot Water Pump Command | ||
| Boiler 1-4 Status | Boiler Status, Boiler Command | ||
| Acceptable Daily Hours of Faulty Operation | Hours | The minimum hours of fault that can trigger an insight | |
| Pump Power Rating | HP | The manufacturer defined rating | |
| Pump Energy Rate | $/kWh | The cost of pump operation per kWh | |
| Weeks of Operation | The annual weeks of operation | ||
| Hot Water Pump Speed | Hot Water Pump Speed | The recorded pump VFD speed |
Notes
1. Expected values for “Pump Status” inputs are “0” or “1”.
2. Expected values for “Boiler Status” inputs are “0” or “1”.
3. Expected values for “Pump Speed” inputs are “100” if they are constant speed pumps or not available.
4. The input(s) that is(are) not used should be set to “0”.
Default Values:
Const. – Threshold for Daily Hours of Faulty Operation[hours]: 2
Const. – Pump Power Rating [HP]: 10
Const. – Pump Energy Rate [$/kWh]: 0.1
Const. – Weeks of Operation: 26