E36 High

Keston E36 Fault Code

The Keston E36 fault code means: your boiler has stopped working because it has lost the connection to the sensor that monitors the temperature of the water circulating through your heating system.. It appears on 2 Keston models 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: Flow thermistor open circuit/not connected - check the connections and wires to the flow thermistor are intact and connected
Typical repair cost £120-200 (including labour)

Engineer required

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

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Keston models that show the E36 fault code

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

Source

Keston E36 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 7 July 2026