Full Gauge TC-940Ri plus
Two-probe controller that can cool, heat or switch automatically, with temperature- or time-started defrost, fan control, door input, lamp/alarm AUX output and RS-485.
What it is: Refrigeration / heat pump controller. The older TC-940Ri sheet has a different, shorter F list (F01–F33) and is not covered here.
Key combo: Press ▲ and ▼ together 2 s for Fun / F01 (access code). Hold the SET key 10 s for manual defrost.
Full Gauge TC-940Ri plus error codes
| Display | Meaning |
|---|---|
| Er1 | Room (S1) probe disconnected or out of range |
| Er2 | Evaporator (S2) probe disconnected or out of range |
| AHi | High room temperature alarm (F37) |
| ALo | Low room temperature alarm (F35) |
| Opn | Door open alarm |
| PPP | Invalid settings: check and re-enter the parameters |
| dEF On / dEF Off | Defrost started / ended by hand |
| F19 t-2 | After a manual defrost of 2 min or more, the evaporator reading is stored as the defrost end temperature |
| Alr OFF | Buzzer silenced |
| LOC | Keys locked |
| CtL | Control on/off being toggled |
| DEL / FAN | Start-up delay / fan delay after drip |
How to enter service / parameter mode
- Parameters: hold ▲ and ▼ 2 s until Fun shows, release, F01 appears.
- Tap SET on F01 and enter the access code from the manual, then pick functions with ▲/▼, tap SET to view and change.
- Long-press SET until --- to leave.
- Viewing works without the code; changing needs it. A second code from the manual selects °C or °F.
- Manual defrost: hold SET 10 s until dEF On; do the same to end it.
Parameter list
| Code | What it does | Range | Default / typical |
|---|---|---|---|
| F02 | Mode: cooling / heating / automatic | 0–2 | 0 |
| F03 / F04 | Differential in cooling / heating | 0.1–20.0 °C | 1.5 / 1.5 |
| F05 / F06 | Room / evaporator probe offset | -20 to 20 °C | 0 |
| F07 / F08 | Lowest / highest user set point | -50 to 75 °C | -50 / 75 |
| F09 | Start-up delay | 0–999 min | 0 |
| F10 | Defrost type (electric or rack hot gas / plug-in hot gas / other) | 0–2 | 0 |
| F11 | Start defrost by time (0) or evaporator temperature (1) | 0 / 1 | 0 |
| F12 / F13 | Defrost interval in cooling / heating | 1–999 min | 240 |
| F14 | Maximum cooling time before a forced defrost (temperature mode) | 1–240 h | 24 |
| F15 | Evaporator temperature that starts defrost | -50 to 75 °C | -5.0 |
| F16 | Pre-defrost time | 0–90 min | 10 |
| F17 | Pump-down time before defrost | 0–90 min | 0 |
| F18 | Defrost at power-up | 0 / 1 | 0 |
| F19 | Evaporator temperature that ends defrost | -50 to 75 °C | 40.0 |
| F20 / F21 | Maximum defrost time (cooling) / defrost time (heating) | 0–90 min | 45 / 30 |
| F22 | Fans on during defrost | 0 / 1 | 0 |
| F23 | Delay to first defrost | 0–999 min | 0 |
| F24 | Hold display during defrost | no–60 min | 0 |
| F25 | Drip time | 0–30 min | 10 |
| F26 | Fan and compressor restart order after drip | 0 / 1 | 0 |
| F27 / F28 | Fan restart: evaporator temperature / maximum delay | -50 to 75 °C / 0–30 min | 0.0 / 1 |
| F29 | Maximum compressor restart delay after drip | 0–30 min | 0 |
| F30 | Fan mode in cooling/heating | 0–2 | 0 |
| F31 / F32 | Fan on / off time | 0–999 min | 2 / 4 |
| F33 / F34 | Stop fans above this evaporator temperature / restart differential | -50 to 75 °C / 0.1–20 °C | 75 / 2.0 |
| F35 / F36 | Low room alarm / differential | -50 to 75 °C / 0.1–20 °C | -50 / 1.0 |
| F37 / F38 | High room alarm / differential | -50 to 75 °C / 0.1–20 °C | 75 / 1.0 |
| F39 / F40 | Alarm block at power-up / after drip | 0–999 min | 0 |
| F41 | Door-open alarm delay | 0–99 min | 0 |
| F42 | Temperature alarm delay | 0–999 min | 0 |
| F43 | Digital input function | 0–8 | 0 |
| F44 | AUX output: none / alarm / lamp / reversing valve | 0–3 | 0 |
| F45 | Door-closed time before lamp off | 0–999 min | 60 |
| F46 | Door-closed time before night set point | 0–999 min | 90 |
| F47 / F48 | Minimum compressor on / off time | 0–999 s | 0 |
| F49 / F50 | Compressor on / off time with failed S1 | 0–999 min | 20 / 10 |
| F51 | Room probe filter | 0–9 | 0 |
| F52 | Hold time to lock keys (14 = off) | 14–60 s | 14 |
| F53 | Allow control off: never / only unlocked / always | 0–2 | 0 |
| F54 | RS-485 address | 1–247 | 1 |
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: Full Gauge TC-940Ri plus instruction manual. Always check the manual for your exact model and software version.
ServiceModes is not affiliated with Full Gauge or any other manufacturer. Written in our own words from the manufacturer's documentation.
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