BoilerFaultCodesMain E270 Fault Code
The Main E270 fault code means: your boiler has detected that water is not moving through the system correctly, causing it to overheat quickly.. It appears on 1 Main model in our database.
Technical description: Circulation fault (dry fire)
What causes the Main E270 fault?
This fault occurs when the water inside your boiler heats up too quickly because it isn't being moved away into your radiators or hot water tank. The most common reasons are a pump that has seized up, a build-up of sludge blocking the pipework, or air trapped within the system preventing flow.
This fault is frequently seen in autumn when heating systems are switched back on after being idle all summer, which can cause the internal pump to stick.
DIY fix possible
Check that your boiler pressure is between 1 and 1.5 bar on the gauge.Ensure all radiator valves and isolation valves under the boiler are fully open.Gently bleed your radiators to remove any trapped air pockets.Reset the boiler to see if the fault clears.
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Gas Safe Register →Main models that show the E270 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Main E270 fault code information on this page is sourced and cross-checked against the official Main service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026