Hill Phoenix Display Refrigerator Error Code P1: Room Probe
P1, Room probe failure, on a Hill Phoenix CNZLA or CNEZLA merchandiser with the Dixell XR06CX controller means the controller cannot read its room (thermostat) probe. The manual says to check connections before replacing the probe. The compressor then follows the Cy and Cn settings.
Medium: the case runs on a fixed compressor pattern without temperature control, which can put product at risk.
- Code
- P1
- Maker
- Hillphoenix
- Equipment
- Display cases
- Applies to
- CNZLA / CNEZLA single-deck merchandisers with Dixell XR06CX controller
What does Hillphoenix error code P1 mean?
The Dixell XR06CX controls the case temperature from a room probe, which is its thermostat input. If the probe signal is missing or out of range, the controller cannot tell whether the case is warm or cold. It shows P1 and starts a probe alarm a few seconds after the problem begins. With no temperature to follow, the compressor output cannot work as a thermostat, so the manual says it follows the Cy and Cn parameters, which set the compressor on and off times in this situation. The alarm stops a few seconds after the probe works again. The manual, in section 12 of the Dixell instructions, says to check the connections before replacing the probe. It does not describe causes beyond the probe failure itself.
Affected models and control systems
CNZLA and CNEZLA single-deck merchandisers (R-290) with the Dixell XR06CX controller. The alarm is described in Appendix B of the installation and operations manual, section 12 and 12.1 of the Dixell instructions.
Code numbers and their meaning can change between control generations. We match the full model and control before acting on a code.
What you may notice
- P1 shows on the controller display
- The case temperature is not being measured, so it may run warmer or colder
- The compressor cycles on a fixed pattern instead of following temperature
Possible causes
Listed in Hillphoenix's documentation
- Room probe failure
Other likely causes — what usually sits behind error code P1 on this control. A technician confirms which one it is before any part is replaced.
- Probe connector loose or corroded at the controller
- Probe cable pinched or damaged where it leaves the case
- Probe knocked out of its position or moisture inside its tip
- Probe open or shorted from age
Safe checks before calling for service
- Check the case temperature with a separate thermometer to see whether product is at risk.
- Look at the probe cable, where you can reach it without removing panels, for damage or a loose plug.
- Turn the case off for a short moment and on again to see whether P1 clears.
- Note whether P1 comes back and tell the technician what the case temperature is.
How a technician diagnoses error code P1
- Read the display and confirm P1 is the active alarm.
- Check the probe connection at the controller and the cable run.
- Measure the probe's resistance and compare with its table at a known temperature.
- Check the Cy and Cn settings so cycling is acceptable until repair.
- Replace the probe only after the connection checks and resistance test fail, then confirm the display.
- Probe connections are inside the controller area next to the case's electrical supply.
- The Cy and Cn values are part of the controller's parameter set and should be changed carefully by a technician.
How error code P1 differs from similar codes
P1 is the room probe and P2 is the evaporator probe on the same controller. HA, LA and the other alarms are temperature or input alarms.
Technical reference
- Document
- CNZLA/CNEZLA (R-290) Single-Deck Merchandiser Installation & Operations Manual, Appendix B Dixell XR06CX operating instructions
- Edition
- P117904D, Rev 1.04, 01/25
- Models / control
- CNZLA / CNEZLA single-deck merchandisers with Dixell XR06CX controller
- Section
- Appendix B2-B3 Dixell Operating Instructions, section 12 Alarm Signalling and 12.1 Alarm Recovery (PDF pp. 42-43); section 8 Digital Inputs
- Checked
- October 2026
We use the maker's document to read the code and do not reproduce it. Always confirm the complete model and control before applying these steps.
Related Hillphoenix display case error codes
Will the case keep cooling with P1?
The manual says the compressor output follows the Cy and Cn parameters, so it runs on a fixed pattern and may not hold temperature well.
Should I replace the probe straight away?
The manual says to check the connections first, as a loose plug is a common reason.
Will P1 clear itself?
The manual says probe alarms stop a few seconds after the probe works again.
Need help with Hillphoenix error code P1?
A technician confirms the cause on site and gives you the price in writing before any work starts.