BoilerFaultCodesWhat the manual says
Manufacturer manualFlow heating thermistor fault
What causes this fault?
This fault occurs when the boiler's main control board loses communication with the sensor that monitors the temperature of the water sent to your radiators. The most common reason is that the sensor itself has suffered an internal electrical failure, or the wiring connecting it to the brain of the boiler has become loose or damaged. Without this data, the boiler shuts down as a safety precaution to prevent the system from overheating.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Avoid the next call-out bill
A cover plan would handle faults like F00: no call-out fees, no surprise bills.
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Related fault codes
All 70 fault codes on the Ultracom 35 Store
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