Low
CC on Heatline Sargon 30

Your boiler has lost its connection to an optional outdoor temperature sensor, but this is usually just an informational message and your heating should still work normally.

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 disconnected and OTC disabled

From this model's manual
Verified against the Heatline/Heatline Sargon 24 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 18 fault codes on the Sargon 30

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

F0F1F01F2F02F3F03F4F04F5F05F6F06F07F8F9OC

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