BoilerFaultCodesTechnical description
Filling mode test program
What causes this fault?
This occurs when the boiler is manually or automatically triggered to run its internal filling program to reach the correct operating pressure. It usually happens after the system has been drained for repairs or when the water pressure has dropped too low and needs topping up. While this code is active, the boiler is simply prioritizing getting the water levels right before it starts heating your home again.
DIY fix possible
Wait approximately 15 minutes for the program to finish automaticallyEnsure your filling loop valves are closed once the pressure reaches 1.5 barIf the code persists, press and hold the 'Reset' button (flame icon) for 3 seconds
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