Nova CAT connection kit
Part number: C546K
Description
Nova climate control kit using a CAT5 connection between the CSL Screen Link Module and the 10″ Nova wall controller. Includes COCBH Smart Hub for iZone Home app connectivity.
Up to three CSL modules can be stacked on a single C225 CPU with no additional transformer.
Installation guide
Installation steps
1. Assemble modules
Connect CSL to C225, then attach C325# AC unit module. If using CEXT: C225 → CSL → CEXT → C325#
2. Pair CSL and run CAT5
Pair the CSL to the C225 CPU, then run Cat5e to the CCASLWE Nova wall controller.
3. Wire zone dampers
Connect zone damper motors to C225 zone ports starting at Zone 1 consecutively.
4. Connect AC unit
Wire the indoor unit per the C325# requirements for the installed brand.
5. Power up
Apply power via CT24ACE. Verify status LEDs on all modules.
6. Commission via the Nova
Tap Setup, enter Installer Code, select AC brand, configure each zone.
7. Pair temperature sensors (if fitted)
Install CDTS upstream of all dampers first. In the iZone app: Menu → Devices → + → Sensors → Temp Sensor → select zone → press and hold sensor pair button.
8. Connect to internet
Connect COCBH Smart Hub to Wi-Fi modem after commissioning is complete.
Specifications
| Entry | Description |
|---|---|
| CPU | C225 |
| Power supply | 24VAC 50Hz via CT24ACE |
| Wall controller | CCASLWE — 10″ Nova touch screen (CAT5) |
| Communications | Wired CAN Bus · Wireless 433MHz (iZone proprietary) |
| Number of zones | 0 to 8 (expandable to 14 with CEXT) |
| Operating temperature | Up to 65°C |
Included in
| Part number | Description |
|---|---|
| C225 | 8-zone CPU |
| CT24ACE | 24VAC power supply |
| CSL | Screen Link Module — connects CPU to Nova via Cat5e |
| C325# | AC unit interface module — brand specific |
| COCBH | Smart Hub — manages CPU ↔ Nova communication and iZone Home app |
| CCASLWE | Nova wall controller — 10″ touch screen (CAT5) |
| CDTS | In-duct temperature sensor (required if using zone temperature sensors) |
Related parts
Documents
Troubleshoot guide
Read more
Nova wall controller screen is blank or unresponsive
The Nova or Nova Mini touch screen fails to power on or goes black.
Steps to resolve:
- Check the power supply (CTDC12) connection to the Nova wall controller
- Check the Cat5e cable between the CSL Screen Link Module and the Nova — try a different port on the CSL
- Re-pair the CSL to the C225 CPU if the connection has been lost
- Replace the cable if the issue persists
- If still unresolved, contact your installer — the CSL or C225 CPU may need to be replaced
Zones are not opening or responding
One or more zones are unresponsive when commanded from the Nova wall controller.
Steps to resolve:
- Move the zone motor cable to a different port on the C225
- In the Nova app, go to Setup → Configure AC → Options → Skip Zone Port (password:
wamfud) and skip the faulty port - Verify the CT24ACE transformer is powered and outputting ~24VAC
- Check all wiring connections are fully seated
Note: On Daikin systems, it can take up to two minutes for dampers to open after a command is sent.
Nova controller not communicating with C225 CPU
The Nova wall controller shows no connection to the system.
Steps to resolve:
- Confirm the COCBH Smart Hub is powered and the Nova shows the Wi-Fi symbol
- Re-pair the CSL to the C225 if pairing has been lost
- Ensure the Smart Hub was not connected to the internet modem before commissioning was completed — if it was, disconnect it, factory reset the COCBH, and recommission the system
- Add a repeater (CR) if the Smart Hub is out of range of the C225
Temperature sensor not showing actual temperature
A zone shows no temperature reading despite having a sensor fitted.
Steps to resolve:
- Press the button on the sensor — if no lights appear, the battery needs replacing (CR2032)
- If the sensor flashes instead of showing solid red or blue, it needs re-pairing: press and hold the pair button, then pair through Menu → Devices in the iZone app
- Ensure the CDTS in-duct sensor is installed upstream of all dampers in the supply air duct
- Check the sensor is not obstructed by furniture or exposed to direct sunlight
Firmware history
Read more
- Added TCL ducted AC integration
- Fixed Brivis reset command and quick on/off issue
- Added AC On with Zone feature
- Added zone grouping (Daikin only)