BoilerFaultCodesWhat the manual says
Manufacturer manualTurbine signal delay (combi only)
From this model's manual
Verified against the Worcester Bosch Greenstar Cdi Compact installation & service manual.
What causes this fault?
This fault occurs when the boiler's internal sensor fails to detect water moving through the system quickly enough after you open a tap. It is usually caused by a sticking flow turbine that can't spin freely or a failing diverter valve that is struggling to switch the water flow from heating to hot water mode.
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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