BoilerFaultCodesVaillant d.10 Fault Code
Also written as D10 — same fault.
The Vaillant d.10 fault code means: your boiler is currently reporting whether the internal water pump is running or stopped, which is a status message rather than an active error indicating a system failure.. It appears on 38 Vaillant models in our database.
Technical description: Pump status 1=ON; 0=OFF
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Vaillant models that show the d.10 fault code
Click a model for the full fault code list and model-specific repair notes.
- Atmomax Repair: £220-450
- ecoFIT Pure 418
- ecoFIT Pure 425
- ecoFIT Pure 435
- ecoFIT Pure 825 Repair: £250-450
- ecoFIT Pure 830 Repair: £200-400
- ecoFIT Pure 835
- ecoMAX Repair: £150-350
- ecoMAX 613 Repair: £180-350
- ecoMAX 618 Repair: £150-350
- ecoMAX 622 Repair: £150-350
- ecoMAX 635 Repair: £200-450
- Ecomax Condensing 600/800 series Repair: £150-£350
- ecoMAX System 612 Repair: £180-350
- ecoTEC 65kW
- ecoTEC plus 412 Repair: £180-350
- ecoTEC plus 415 Repair: £180-350
- ecoTEC plus 418 Repair: £180-350
- ecoTEC plus 424 Repair: £180-350
- ecoTEC plus 430 Repair: £180-350
- ecoTEC Plus 610 Repair: £180-350
- ecoTEC Plus 615
- ecoTEC Plus 620
- ecoTEC Plus 625
- ecoTEC Plus 635
- ecoTEC Plus 840
- ecoTEC plus aquaPLUS
- ecoTEC sustain
- Home Combi Repair: £200-450
- Home System
- Thermocompact
- Turbomax 824/828 Repair: £150-300
- Turbomax Plus Repair: £150-350
- Turbomax Plus 824/828E
- Turbomax Plus 828 Repair: £150-350
- Turbomax Plus 828 E
- Turbomax Plus VUW 242E
- Turbomax Plus VUW 242EH
Source
Vaillant d.10 fault code information on this page is sourced and cross-checked against the official Vaillant service / installation manuals for each affected model.
- Vaillant ecoFIT Pure 425 manual (PDF)
- Vaillant ecoFIT Pure 835 manual (PDF)
- Vaillant Ecomax Condensing 600/800 series manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 31 August 2026