Ideal Logic F1 fault code: what low water pressure means

What Does Error F1 Mean?

Ideal defines F1 as low water pressure in the sealed heating system, and the boiler stops until the pressure is raised. Ideal tells the owner to check the gauge reads between 1 and 1.5 bar and to repressurise with the filling loop if it is low, then to call a Gas Safe registered engineer if the pressure keeps dropping. Applies to: Ideal Logic, Logic Max, and Logic Plus boilers that display F1 This applies to Ideal Logic family boilers whose published fault guidance lists F1. Ideal uses L1 for a flow overheat or no-flow condition, which is a different branch, so read the exact characters on the display before acting. Owner-safe checks: With the boiler off and cool, read the pressure gauge and top up to about 1.5 bar with the filling loop only if it is below 1 bar. | After topping up, close both filling-loop valves fully and check whether the pressure holds over the next day of normal heating. Qualified technician: A pressure that will not hold, visible leaks or staining, an expansion vessel check, or an F1 that alternates with L1 needs a Gas Safe registered engineer.