BoilerFaultCodesTechnical description
Collector temperature sensor (T1) fitted on collector array inlet.
What causes this fault?
This fault occurs when the sensor on your roof's solar panels detects that the fluid has become too hot or if the sensor itself has developed an electrical failure. It is often caused by a lack of fluid circulation in the solar circuit or a degraded sensor that is sending incorrect temperature readings to the boiler.
This fault is most common during the summer months when high levels of solar radiation can lead to the solar fluid overheating if the system isn't circulating correctly.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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