High
No Water Flow on Ideal Logic+ HEAT2 H12

Your boiler has temporarily stopped because it cannot detect enough water moving through the system to keep it cool and safe.

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

No Water Flow

From this model's manual
Verified against the Ideal/Ideal Orig Ideal Logicplus Heat2 Installation Servicing 09 2024 installation & service 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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Related fault codes

F1View →F2View →L2View →

All 17 fault codes on the Logic+ HEAT2 H12

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

Blocked Flue/CondensateFan FaultFlame LossFlame On Before Gas OnFlow Thermistor FaultFlow/Return ReversedGas Valve FaultIgnition LockoutLow Mains VoltageOutside Sensor FaultOverheat LockoutPCB FaultReturn Thermistor FaultRoom Thermostat FaultSpare PCB Not SetToo Many Restarts

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