High
Loss of system water pressure on Ideal Classic Slimline FF 330 360

Your boiler has lost the water pressure it needs to circulate heat, likely because there is a small leak somewhere in your radiator pipes or the boiler itself.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

What the manual says

Manufacturer manual

If the red arrow on the system pressure gauge is set above zero and the system pressure is seen to fall below this value over a period of time then a water leak is indicated.

Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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All 5 fault codes on the Classic Slimline FF 330 360

Seeing a different code? Every code this model can display, in one place.

Neon I3Neon l3Neon SG1Overheat thermostat

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