BoilerFaultCodesTechnical 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