Unical error codes
The complete list of Unical fault codes shown on the display, each with what it means and the page that explains how it is diagnosed and fixed.
Unical heating appliances display 25 documented error codes. Each code below opens its own page with the official meaning, the documented causes, the safety assessment and the parts involved.
All Unical Error Codes
25 codes, each with its own page. Click a code to open the meaning, the documented causes and the repair.
What Fails Most Often on Unical
Grouped from the official meaning of each of the 25 codes above — not from opinion. The number is how many different fault codes point at that component.
| Component | Codes | Examples |
|---|---|---|
| Ignition | 7 | 04, 05, 11, 17 |
| Pump | 3 | 15, 21, 40 |
| Temperature Sensor | 3 | 22, 58, 80 |
| Pressure Switch | 2 | 02, 2 |
| Overheat | 2 | 06, 19 |
| Water Pressure | 2 | 08, 44 |
Parts & Prices
The parts most often involved in the Unical faults listed above.
Prices and availability vary by region and are shown by the retailer, not by TroubleAtlas.
Diagnostic Tools
What an engineer uses to work through the codes on this page.
TroubleAtlas Pro
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Considering a New Heating System?
If your Unical appliance is over 10 years old, replacing it with a modern condensing boiler or air-source heat pump could cut energy bills and remove the recurring faults listed on this page.
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