BoilerFaultCodesYour boiler has detected that the solar collector probe is in an open circuit, meaning it cannot properly monitor the temperature of your solar heating system if you have one connected.
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: Clas HE evoClas he evo systemE-combi evoE-system evo
What causes this fault?
This fault occurs when the boiler loses communication with the sensor that monitors your solar heating panels. It is usually caused by a loose connection, damaged wiring between the boiler and the panels, or a sensor that has developed an internal electrical failure. When this happens, the system can no longer tell how hot the solar water is, preventing it from integrating with your heating efficiently.
This fault is more common in summer when the solar heating system is under peak load and high temperatures can strain a degrading sensor or wiring.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 208 — no call-out fees, no surprises.
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