In-duct temperature sensor
Part number: CDTS
Description
The CDTS monitors the supply air temperature inside the ductwork. It is required on any system that uses iZone zone temperature sensors for climate control. It tells the C225 when to reverse damper action between heating and cooling modes.
warning
The CDTS is only required when zone temperature sensors (CRFSW, CRFS2, or CSW) are used. It is not needed for open/close-only zone systems.
Installation guide
Installation steps
- Install the CDTS in the supply air plenum as close to the FCU discharge as possible, upstream of all zone dampers
- Insert the probe fully through the duct wall and secure with reinforced aluminium tape
- Seal around the probe entry point with aluminium tape to prevent air leaks
- Connect the RJ11 cable to the CDTS port on the C225 — not a zone port
- Power on the system and verify the CDTS shows a live reading in Setup → Sensors
Specifications
| Entry | Description |
|---|---|
| Model number | CDTS |
| Power supply | Powered from C225 via RJ11 |
| Connection | RJ11 |
| Temperature range | -14 to 85°C |
| Cable length | ~3000 mm |
| Weight | 50 g |
Included in
Sold separately. Required on any C225-based system using zone temperature sensors.
Related parts
Documents
Troubleshoot guide
Read more
CDTS not showing temperature in app
- Check the RJ11 cable is seated in the CDTS port on the C225 — not a zone port
- Try a different RJ11 cable to rule out a cable fault
- The sensor may take up to 60 seconds after power-on to appear
Firmware history
No firmware — the CDTS is a passive sensor with no embedded software.