BoilerFaultCodesVokera E48 Fault Code
The Vokera E48 fault code means: your boiler has detected that the exhaust gases are getting too hot, causing the fan to run at full speed to protect the system from damage.. It appears on 1 Vokera model in our database.
Technical description: Flue gas probe error for having exceeded the temperature limit (with this error, the fan operates at max.)
What causes the Vokera E48 fault?
This fault occurs when the internal sensors detect that the exhaust gases have reached a dangerously high temperature, which is often a sign that heat isn't being transferred effectively to the water. The most common reasons are a heavy buildup of limescale or debris inside the heat exchanger, or a physical blockage within the flue pipes preventing proper ventilation.
This issue often comes to light during the first cold spell of autumn or winter when the boiler is required to run at maximum output for long periods.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Vokera models that show the E48 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Vokera E48 fault code information on this page is sourced and cross-checked against the official Vokera service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026