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:

1. Navigate to the Excel10 device in your station

2. Expand the device to find the flow-related properties

3. Look for properties like:

   • flowKFactor
   • kFactor
   • Or similar under the AX property sheet

4. 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:

1. Use Honeywell's CARE tool for direct device access
2. Check if the value is read-only from the LON network
3. 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