BoilerFaultCodesYour boiler’s solar heating connection has a faulty sensor that is incorrectly detecting a short circuit, preventing your solar panels from helping to heat your water.
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: Control mode - Solar: Sensor S3 shorted out
What causes this fault?
This fault occurs when the electrical resistance in the solar temperature sensor falls outside of its normal range, signaling a short circuit to the boiler. The most common reasons are internal failure of the sensor itself or physical damage to the wiring, such as water ingress or frayed cables, which prevents the system from accurately reading the solar tank temperature.
This fault may be more noticeable during the summer months when high temperatures inside the solar circuit can accelerate the wear and tear of aging thermal sensors.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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