BoilerFaultCodesYour boiler's internal sensor has detected a communication issue with your solar heating system, meaning the solar panels aren't currently 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: Temperature sensor type PTC 1000 used as collector temperature sensor (T1).
What causes this fault?
This fault occurs when the boiler loses contact with the sensor located on your roof's solar panels. The most common reasons are a faulty temperature sensor or a break in the wiring that connects your solar thermal system to the boiler's control module. Without this communication, the boiler cannot determine how much heat is available from the sun and will stop using the solar system.
This fault is more common following extreme weather events, as high winds or heavy snow can damage the external wiring or sensor probes located on the roof.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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