BoilerFaultCodesKeston E41 Fault Code
The Keston E41 fault code means: your boiler's main control panel is having trouble talking to the internal computer, which is preventing the system from starting up.. It appears on 9 Keston models in our database.
Technical description: Communication error between fascia and control box – check cables
What causes the Keston E41 fault?
This fault occurs when the digital signals sent between the boiler's front display panel and the main internal computer are interrupted. The most common reason is a loose or damaged connection cable, though it can also happen if moisture gets behind the casing or if one of the electronic circuit boards has suffered a hardware failure.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Keston models that show the E41 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Keston E41 fault code information on this page is sourced and cross-checked against the official Keston service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026