Primary air system is cooling while discharge air temperature is below setpoint

Objective/Method/Outcome

Objective: Determines if the Supply Air Temperature is below setpoint when Primary Air System is cooling

Method: Compares the supply air temperature to the setpoint to see if it was below the acceptable range while the cooling valve is open.

Outcome: Triggers an insight.

Applicable System

SAT

Description

Monitors cooling valves within primary air system units, ensuring they are closed when SAT is sufficiently below setpoint.

This rule is part of the CopperTree Standard ruleset.

Diagnosis

  1. Cooling may be manually overridden.
  2. Review control loop tuning.
  3. Temperature sensor may need calibration.

Message

Unit is cooling while SAT is sufficiently below setpoint.

Default Priority

Low

Rule Template

Insight Type: Energy

Trigger Type: Active High

Logic

Logic for determining if primary air system is cooling when DAT is below setpoint

Inputs

Input Unit Tags Description
Supply Air Temperature   Discharge Air Temperature The recorded supply air temperature
Supply Air Temperature Setpoint   Discharge Air Temperature Setpoint, Discharge Air Temperature Cooling Setpoint The ideal supply air temperature
Cooling Valve   Discharge Air Cooling Command The status of the discharge air cooling status
Supply Air Temperature Deadband °    
Threshold – Weekly Hours of Faulty Operation     The minimum hour of fault that can trigger an insight

Notes

Default Values:

  • Supply Air Temperature Deadband [°]: 2
  • Threshold – Weekly Hours of Faulty Operation: 8