Interfacing with Honeywell Comfort Point Controllers
This guide covers integrating a front-end system over existing Honeywell Comfort Point (IPC) controllers and VAV controllers.
Comfort Point Architecture Overview
Honeywell Comfort Point systems use:
| Component | Protocol Support | Notes |
|---|
| Comfort Point Open (CPO) | BACnet/IP, LON | Current platform |
| IPC (Integrated Personal Computer) | BACnet/IP, LON | Legacy supervisory |
| Spyder Controllers | LON, BACnet MS/TP | Zone/unitary controllers |
| Excel 10/15 | LON | Legacy zone controllers |
| T7350 Stats | Proprietary to Spyder | Zone sensors |
Integration Approaches
Option 1: BACnet/IP Integration (Recommended)
Most modern Comfort Point systems support BACnet/IP natively.
Architecture:
New Front-End <--BACnet/IP--> Comfort Point Server <--> Field Controllers
Steps:
- Verify BACnet capability - Check CPO software version
- Configure BACnet server on Comfort Point:
- Navigate to System Settings > Communications
- Enable BACnet/IP server
- Set device instance (unique across site)
- Configure IP address/port (default 47808)
- Define exposed points - Select which points to expose via BACnet
- Discover from new BAS - Add as BACnet/IP device
- Map points - Create point references in new front-end
Typical BACnet objects available:
- Zone temperatures (AI)
- Setpoints (AV)
- Occupancy status (BI)
- Equipment status (BI)
- Fan/damper commands (AO)
- Mode selection (Multi-state)
Option 2: BACnet MS/TP Direct to Spyders
If bypassing Comfort Point server and connecting directly to Spyder controllers:
Requirements:
- BACnet MS/TP interface on new front-end
- Physical access to MS/TP trunk
- Knowledge of existing device addressing
Considerations:
- Spyders must have BACnet MS/TP enabled (not all do)
- Check firmware version for BACnet support
- MS/TP segment limits apply (64 devices max)
- May need to install MS/TP router if BACnet/IP preferred
Option 3: LON Integration
For legacy Excel 10/15 or LON-based Spyder systems:
Requirements:
- LON interface (LON-IP router or serial interface)
- SNVT definitions for point mapping
- LNS database or network documentation
Tools:
- LonMaker or equivalent commissioning tool
- LON protocol analyzer (optional but helpful)
Option 4: Hybrid Overlay
Keep Comfort Point operational while adding new front-end:
Benefits:
- No disruption to existing operation
- Gradual migration possible
- Native Honeywell functionality preserved
Implementation:
- New front-end connects via BACnet to Comfort Point
- Both systems operate in parallel
- Eventually deprecate Comfort Point UI (optional)
Point Mapping Considerations
Critical Points to Map
| Category | Points | Priority |
|---|
| Zone Control | Temperature, setpoint, occupancy | High |
| Equipment | Status, runtime, alarms | High |
| Schedules | Occupied/unoccupied mode | Medium |
| Diagnostics | Communication status, errors | Medium |
| Energy | kWh, demand (if metered) | As needed |
Alarm Handling
- Configure alarms in new front-end vs relying on Comfort Point
- Map critical alarms to BACnet event objects if supported
- Test alarm propagation during commissioning
Schedule Coordination
Decide where schedules will live:
- Option A: Schedules in new front-end, Comfort Point follows
- Option B: Schedules remain in Comfort Point, new front-end monitors
- Option C: Synchronized schedules (more complex)
Maintaining Native Functionality
When overlaying a system, preserve these Comfort Point features:
- Local occupancy override at zone
- Demand limiting (if implemented)
- Optimal start/stop sequences
- Fire/smoke integration interlocks
Best practice: New front-end for monitoring/trending, Comfort Point for control execution.
Common Issues
BACnet Discovery Problems
- Verify IP addressing and subnet masks
- Check firewall rules (port 47808 UDP)
- Confirm BACnet server is enabled
- Use BACnet scanning tool to verify visibility
Point Mapping Mismatches
- Units may differ (°F vs °C)
- Scaling factors may need adjustment
- Status bit interpretation varies
Communication Timeouts
- Comfort Point may limit concurrent BACnet connections
- Increase timeout values in new front-end
- Consider polling rate impact on system performance
Documentation Needed
Gather before starting:
- Comfort Point network diagrams
- IP address assignments
- Controller addressing (LON or BACnet)
- Point lists by controller
- Sequence of operations
- Any existing BACnet configuration