Low
i13 on Worcester Bosch Greenstar Heatslave II

This is not an error code, but rather a live status display showing the current temperature of the internal water store inside your boiler.

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

Thermal store current temperature - This is the thermal store current temperature, displayed in real time (rounded to 0.5°C units).

From this model's manual
Verified against the Worcester Bosch Greenstar Heatslave Ii 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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