BoilerFaultCodesWhat the manual says
Manufacturer manualFlow rate in heat exchanger too low 1. Supply sensor is not assembled on the supply pipe. 2. Supply sensor does not make proper contact to the supply pipe. 3. System is not filled with water. 4. No water flow, because CH system is closed. 5. No water flow, because pump is not operating correctly.
From this model's manual
Verified against the Worcester Bosch Greenstar 8000 Life System installation & service manual.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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