Vaillant error codes
The complete list of Vaillant fault codes shown on the display, each with what it means and the page that explains how it is diagnosed and fixed.
Vaillant heating appliances display 147 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 Vaillant Error Codes
147 codes, each with its own page. Click a code to open the meaning, the documented causes and the repair.
What Fails Most Often on Vaillant
Grouped from the official meaning of each of the 147 codes above — not from opinion. The number is how many different fault codes point at that component.
| Component | Codes | Examples |
|---|---|---|
| Pump | 19 | D10, D12, D13, D14 |
| Ignition | 19 | D64, D65, D68, D69 |
| Temperature Sensor | 18 | D4, F.03, F.13, F.45 |
| Fan | 10 | D33, D34, E4, F.32 |
| Return Sensor | 9 | F.01, F.71, F.83, F.84 |
| Gas Valve | 6 | F.26, F.61, F.62, F.88 |
| Water Pressure | 6 | F.72, F.73, F.74, F73 |
| Control Board | 5 | F.64, F.65, F.97, F65 |
Parts & Prices
The parts most often involved in the Vaillant 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 Score — Vaillant
How Vaillant scores
Independently assessed across six dimensions from the documentation, the fault codes and the parts network. Based on 131 error codes across 52 appliances.
How we calculate it →TroubleAtlas Pro
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Considering a New Heating System?
If your Vaillant 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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