Low
Er 19 on Biasi Advance 25C

Your boiler is having trouble measuring the temperature of the cold water coming in, which may affect how well it heats your hot water.

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.

Technical description

Domestic hot water inlet probe failure (if present)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

Er 05View →Er 06View →

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