VAV damper is consistently at 100%

Objective/Method/Outcome

Objective: Determines if the VAV damper is consistently 100% open during operational hours.

Method: Compares the VAV damper command to the error threshold to find the hours during which the valve is open at 100%. This is compared to the hours of operation to determine if the damper is consistently at full capacity and find the avoidable cost of running the system at 100%.

Outcome: The rule triggers an insight and calculates potential savings.

Applicable System

VAV

Description

Damper control: Check for VAV dampers constantly at 100%.

This rule is part of the CopperTree Standard rule-set.

Default Priority

Medium

Diagnosis

  1. Verify damper control – could be manually overridden.
  2. Verify if the damper is stuck open.

Message

VAV damper is 100% open for more than 95% of the total weekly occupied hours. Please review damper operation.

Rule Template

Insight Type: Fault Detection

Trigger Type: Active High

Logic

Logic for determining if VAV damper is at 100%

Inputs

Input Unit Tags Description
Occupancy Room Occupied, Discharge Fan Command, Discharge Fan Status
Threshold – Acceptable Weekly Percent % The weekly acceptable percentage of time the VAV can operate at 100%
Threshold – Damper Fully Open % The minimum damper position that can trigger insight
Damper Position  Discharge Air Volume Damper, Discharge Air Volume Damper Position The position of the damper

Notes

Default Inputs:

  • Threshold – Acceptable Weekly Percent [%]: 95%
  • Threshold – Damper Fully Open [%]: 98%