BoilerFaultCodesYour boiler's hot water system has lost communication with the temperature sensor in your solar cylinder, meaning it cannot accurately monitor the water temperature.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Temperature sensor T2 at bottom of solar cylinder faulty: Break in the sensor lead (T2).
What causes this fault?
This fault occurs when the electrical connection between your boiler and the hot water cylinder's solar sensor is interrupted. The most common reasons are a physically damaged or degraded sensor wire, or the internal components of the sensor failing due to long-term exposure to heat and moisture.
This fault may become more apparent during the summer months when the solar thermal system is most active and the boiler relies heavily on these readings to manage hot water production.
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 Fault 41 / 104 — no call-out fees, no surprises.
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