Low
OC on Heatline Vizo Plus

Your boiler has detected an outdoor temperature sensor and is automatically adjusting its settings to match the weather outside.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

External sensor is connected and OTC enabled

From this model's manual
Verified against the Heatline Vizo Plus installation & service manual, page 27.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

No action is required as this is an advisory notification rather than a breakdown.Check your thermostat settings to ensure the heating is coming on at your preferred times.If you did not intend to have an outdoor sensor, contact a technician to check the wiring.

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