Low
i7 on Worcester Bosch Greenstar Heatslave II

Your boiler is displaying its current target heating temperature rather than an error message, which is normal operation while the system is waiting for a signal to provide heat.

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

CH flow temperature set point - This is the temperature set point for the primary flow from the main heat exchanger. This will be zero during CH demand.

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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