Dixell and Carel Walk-In Controller Alarm Codes

Dixell and Carel controllers show up on many walk-ins, especially where an installer or equipment maker built the controls rather than using a refrigeration brand's own controller. They are reliable, but their codes are short, easy to misread, and specific to each model.

The tables below come from the official manuals for two widely used models: the Dixell XR60CX and the Carel ir33 platform. Codes are model-specific. If your controller is a different model, look up the code in that model's manual before acting on it.

First, confirm the brand and model

Look for the brand and model on the controller face or on a label on its side or back. Common walk-in examples are the Dixell XR series and the Carel ir33 family, but both companies make many models. Photograph the label and the display.

Tip: The code "HA" is the classic trap. On the Dixell XR60CX, HA is the maximum (high) temperature alarm. On the Carel ir33, HA is a HACCP alarm, and the high-temperature alarm is "HI." Reading a Carel HA as "the box is warm" or a Dixell HA as "just a logging note" can lead to the wrong response.

Dixell XR60CX codes

Source: Dixell XR60CX manual (r1.1, 27 Apr 2015), pp.3–4.

How they clear: probe alarms clear a few seconds after the probe reads normally again. HA and LA clear when the temperature returns to normal.

Other messages: Pon and PoF mean the keyboard is unlocked or locked. noA means no alarm is recorded.

About CA: when CA comes from a pressure switch (PAL), the controller turns everything off and recovers only after a power cycle. That protects the compressor. Power-cycling repeatedly to get cooling back, without finding why the pressure switch opened, risks the compressor. See pressure controls.

Carel ir33 codes

Source: Carel ir33 user manual (+030220441 rel. 2.5, 16 Jun 2010), Table 8.a, p.59. Some Carel families share this code set; check your own model's manual.

Watch the look-alikes:

• E1 on Carel is a defrost probe fault. On a Heatcraft Beacon II, E1 is the room sensor. Different brands, different meanings.
• dA on Carel is a delayed external alarm. On Dixell, dA is door open. Carel's door alarm is dor.
• dEF on Carel means defrost is running, which is normal.
• Ed1/Ed2 mean defrost ended on the timer instead of the probe. Occasional timeouts can be normal; frequent ones suggest a coil icing or a probe problem. See defrost system.

What to do when a code appears

1. Record the code and photograph the display.
2. Check the box temperature with a separate thermometer in the warmest part of the box. A probe fault means the display may be wrong.
3. Rule out normal events: defrost (dEF), a door left open, or a recent delivery.
4. For high-temperature alarms, protect product first. See walk-in cooler temperature alarm.
5. Call a licensed technician for probe faults, pressure or condenser alarms, repeated defrost timeouts and memory or clock errors.

Settings staff should not change

Both brands have long parameter lists behind the setpoint: alarm limits, alarm delays, probe offsets (calibration), defrost interval and duration, fan behavior, door and digital input settings, compressor protection timers and the backup cycle used when a probe fails (Con and COF on the Dixell). A single wrong parameter can stop defrost, disable an alarm or freeze product.

• Don't change parameters to silence an alarm. Raising the high alarm limit or lengthening a delay hides a problem that's still there.
• Don't change probe offsets to "correct" a reading. If the display disagrees with a calibrated thermometer, have the probe checked. See thermostat and temperature controller.
• Don't change input settings such as i1F on the Dixell. It decides whether an input is treated as a door switch, an external alarm or a pressure switch.
• Do record the current settings before a technician changes anything, so they can be put back.
• Do keep the keypad locked if the controller supports it (Pon/PoF on the Dixell).

Safety: Don't open the controller housing or the electrical panel it's mounted in. Many controllers switch line-voltage loads directly.

For how controller alarms fit together across brands, see walk-in controller alarm codes. If your walk-in uses Heatcraft's own controller, see Heatcraft controller troubleshooting. For general troubleshooting beyond the controller, see the walk-in cooler troubleshooting guide.