44
FAULT CODE
Alpha
Safety Lockout — External Control Cycling
Medium Severity
DIY Check Possible
The boiler has locked out due to too many rapid on/off requests from an external control (room thermostat) or rapid hot tap usage.
Step-by-Step Fix Guide
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Step 1
Check that the room thermostat is not cycling rapidly — it should maintain a stable setpoint
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Step 2
Avoid rapidly turning hot taps on and off
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Step 3
Reset the boiler
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Step 4
If fault persists, the thermostat may need replacing — call a heating engineer
Gas Safe Reminder
Work on gas appliances must be carried out by a Gas Safe registered engineer. The steps above cover safe checks a homeowner can perform - any internal component replacement requires a qualified professional. If in doubt, always call an engineer.