Air Balancing Honeywell Excel10 VAVs in Niagara N4
Topic: Niagara/Tridium, LON Integration
Difficulty: Advanced
Overview
Adjust K factors on Honeywell Excel10 VAV boxes integrated with Niagara N4 for proper air balancing. This guide covers accessing and modifying flow calibration parameters.
The Question
Is it possible to change a K factor on an Excel10 VAV in N4 via the device's AX property sheet?
Environment
- Vykon JACE 9000 with Niagara 4.13.2
- Honeywell Excel10 VAVs on LON network
Understanding K Factors
The K factor is a calibration constant used to convert velocity pressure readings to CFM (cubic feet per minute). Each VAV box has a unique K factor based on:
- Box size
- Inlet configuration
- Sensor location
Solution: Modifying K Factor
Yes, you can modify the K factor through Niagara:
-
Navigate to the Excel10 device in your station
-
Expand the device to find the flow-related properties
-
Look for properties like:
flowKFactor
kFactor
- Or similar under the AX property sheet
-
The property is typically under:
Drivers > LonNetwork > Excel10Device > AX > Flow > KFactor
Important Considerations
- Backup first: Export device configuration before changes
- Document original values: Record existing K factors
- Verify after change: Confirm new value is written to device
- Field verification: Use a balancing hood to verify actual CFM
Alternative Methods
If the property isn't directly accessible:
- Use Honeywell's CARE tool for direct device access
- Check if the value is read-only from the LON network
- Some parameters require local device programming
Troubleshooting
- Property not writable: Check LON binding configuration
- Value doesn't persist: Verify device accepts writes
- CFM still incorrect: Validate sensor wiring and pressure readings
Related Topics
- BACnet integration
- LON network configuration
- VAV control strategies