Carel ir33 Universal

General-purpose controller for temperature, humidity, pressure and similar loops, with two set points, up to four outputs and P, PI or PID control.

What it is: Universal controller (heating, cooling, PID). Two-probe, multi-output universal version of the ir33.

Error codes ↓
Parameters ↓

Carel ir33 Universal error codes

Code	Meaning	Likely cause	How to reset
E01	Probe B1 fault	Probe open or shorted, wrong probe type (c13)	Clears by itself.
E02	Probe B2 fault	Probe open or shorted, wrong probe type	Clears by itself.
E03	Digital input open	Input set as external alarm has opened (immediate, delayed or manual-reset type)	Automatic, or manual for the manual-reset types.
E04	High temperature alarm, probe 1	Above P26	Clears by itself.
E05	Low temperature alarm, probe 1	Below P25	Clears by itself.
E06	Real-time clock fault	Clock lost or not set	Automatic or manual. Set the clock (tc).
E07	Unit parameter memory error	EEPROM fault	Clears by itself if it goes away.
E08	Operating parameter memory error	EEPROM fault	Clears by itself if it goes away.
E09–E15	PID auto-tuning errors	Auto-tune could not finish, or calculated gains/times are invalid, or conditions were not right to start	Manual reset. Check the loop and retry auto-tune (c64).
E16	High temperature alarm, probe 2	Above P31	Clears by itself.
E17	Low temperature alarm, probe 2	Below P30	Clears by itself.
E18	Digital input open (signal only)	Input set to signal only	Clears by itself.
E19	Digital input open, circuit 2	Input set as circuit 2 alarm	Automatic or manual depending on setting.

Parameter list

Code	What it does	Range	Default / typical
St1 / St2	Set point 1 / 2	c21–c22 / c23–c24	20 / 40
c0	Operating mode: 1 all direct (cooling), 2 all reverse (heating), 3 half and half, 4 PWM, 5 alarm, 6–9 mode change or two set points from the digital input	0–9	2
P1 / P2	Differential 1 / 2	0.1–99.9	2.0 / 2.0
P3	Dead zone differential	0–99.9	2.0
c4	Compensation coefficient (modes 1 and 2)	−2 to 2	0.5
c5	Control type: 0 P, 1 PI	0–1	0
c6	Delay between stage starts	0–255 s	5
c7	Minimum time between starts of the same output	0–15 min	0
c8 / c9	Minimum off / on time for each output	0–15 min	0
c10	Output state with a probe fault (0 all off, 1 all on, 2 cool on heat off, 3 cool off heat on)	0–3	0
c11	Output rotation	0–7	0
c13	Probe type (0 NTC, 1 NTC high temp, 2 PTC, 3 Pt1000 … 7–10 thermocouples, 11–16 voltage/current)	0–16	0
P14 / P15	Probe 1 / 2 calibration	−99 to 99.9	0
c18	°C (0) or °F (1)	0–1	0
P25 / P26	Probe 1 low / high alarm threshold	−199 to 800	−50 / 150
P27 / P28	Probe 1 alarm differential / delay	0–99.9; 0–250 min	2 / 120
P29	Probe 1 alarm type (0 relative, 1 absolute)	0–1	1
c29 / c30	Digital input 1 / 2 function	0–12	0
c50	Keypad / remote lock (0 keypad off, 1 all on, 2 all off)	0–2	1
c64	PID auto-tuning (1 = on)	0–1	0

Notes

The source is a distributor's summary sheet, so confirm critical settings on the controller.
c51 is marked by Carel as a special mode that should not be changed.
The summary sheet does not describe the keypad procedure, so it is not repeated here. See the Carel ir33 Universal manual for menu access.

For licensed technicians only. This equipment can involve mains voltage, high-voltage microwave circuits, gas and refrigerant. Isolate power (and gas) before opening panels, follow the manufacturer's manual and your local licensing rules (for example ARC refrigerant handling and electrical or gas licences). Wrong settings can spoil food or damage equipment. Check every value on the unit in front of you before changing it.

Based on: Carel ir33 Universal parameter summary (+AU00IR33U rev 2.0). Always check the manual for your exact model and software version.

ServiceModes is not affiliated with Carel or any other manufacturer. Written in our own words from the manufacturer's documentation.

Carel ir33 Universal

Carel ir33 Universal error codes

Parameter list

Notes

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