High
No flow on Ideal Concord Cxdi

Your boiler has stopped working because it cannot detect that water is moving through the system as it should.

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 a flow switch is not connected to the boiler a link should be fitted between the 2 terminals for the flow switch. If the terminals are left disconnected the display will indicate 'No flow' and the boiler will not operate.

From this model's manual
Verified against the Ideal Concord Cxdi 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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