What does the Worcester Bosch Blue light off fault code mean?

Your boiler currently has no power, which means it cannot provide hot water or heating until the electrical connection is restored.

How much does it cost to fix Worcester Bosch error code Blue light off?

Typical repair cost for the Worcester Bosch Blue light off fault is £100-250 including labour.

Check that the main boiler power switch, the fused spur, and the thermostat are all switched on.

External control or internal frost thermostat is not calling for heat, or No power to the boiler / Internal fuse blown

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Work through these before the call-out.

Almost always a stuck diverter valve on combis.

Safety-critical — turn off, read this.