D1 286 High

Worcester Bosch D1 286 Fault Code

Also written as D1286 — same fault.

The Worcester Bosch D1 286 fault code means: your boiler has detected that the water returning to it is too hot, causing it to shut down to prevent damage from overheating.. It appears on 1 Worcester Bosch model in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Return temperature too high - Boiler overheat
Typical repair cost £150-300 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Worcester Bosch models that show the D1 286 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Worcester Bosch D1 286 fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026