High
NO DISPLAY on Johnson Starley Warmcair DW

Your boiler has lost power entirely, which is usually caused by a tripped switch at the fuse box or a fault with the electrical supply to the unit.

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

Lack of 230V AC supply to heater or loose wiring between terminal block and main PCB.

From this model's manual
Verified against the Johnson Starley Warmcair Dw 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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