BoilerFaultCodesAlpha 0E37 Fault Code
The Alpha 0E37 fault code means: your boiler has stopped working because the water pressure inside the heating system has dropped too low.. It appears on 3 Alpha models in our database.
Technical description: Insufficient system pressure.
What causes the Alpha 0E37 fault?
This fault occurs when the water level inside your central heating system drops below the minimum level required for the boiler to operate safely. The most common reasons for this are a small leak somewhere in your radiator pipework or the air being released from the system through a valve.
This fault is frequently seen in autumn or winter when the heating is turned on for the first time after being dormant for several months.
DIY fix possible
Locate the internal filling loop, which is usually a small silver braided hose or a plastic key located underneath the boiler.Open the filling valve slowly to let water into the system until the pressure gauge on the front of the boiler reads between 1.0 and 1.5 bar.Close the valve tightly to stop the flow of water and ensure the boiler resets itself automatically.
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Gas Safe Register →Alpha models that show the 0E37 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Alpha 0E37 fault code information on this page is sourced and cross-checked against the official Alpha service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026