BoilerFaultCodesYour boiler is having trouble communicating with the solar heating controls, which may prevent your hot water from reaching the desired temperature.
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.
Technical description: In conjunction with Vitosolic solar control unit: Set DHW value 3
What causes this fault?
This fault happens because the main boiler computer has lost its digital connection with the solar heating control panel. It is usually caused by a loose communication cable between the two units or a electronic failure within the solar module itself. When this link breaks, the boiler doesn't know how much heat the solar panels are providing, which can lead to inefficient water heating.
This issue is often more noticeable during the spring and summer months when homeowners expect their solar panels to handle the majority of their hot water production.
DIY fix possible
Locate your boiler's power switch and turn it offWait for 30 secondsTurn the power back on to see if the communication fault clears
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