High Lockout
F1 on Ideal Logic Combi ESP1

Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Low Water Pressure

What causes this fault?

This fault occurs when the water pressure inside your heating system drops below a safe level, causing the boiler to shut down to prevent internal damage. The most common reasons are a slow leak from a radiator valve or pipework, or air being released from the system through recent bleeding of radiators.

This issue is more frequent in autumn when homeowners turn their heating back on for the first time, as small leaks may have developed or settled during the summer months.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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