High
Red Neon on Potterton Ultra 2 30 DV

Your boiler has detected a problem and safely shut itself down to prevent damage, meaning you currently have no heating or hot water.

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

The red neon will light if the boiler has locked out.

From this model's manual
Verified against the Potterton/Potterton Ultra 2 50 Dv 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

LockoutView →

All 8 fault codes on the Ultra 2 30 DV

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

FlameGreen neonLockoutPermanent LiveReversed PolaritySwitched LiveThermostat +

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