BoilerFaultCodesTechnical description
Flow temperature abnormally high. Check pump, 3-way valve & CH system pressure. Replenish system, adjust pump speed & bleed air
What causes this fault?
This fault occurs when the boiler's internal sensors detect that harmful exhaust gases are not being cleared away correctly or that the flue is getting too hot. The most common reasons include a blockage in the flue pipe, a failing fan that cannot push the fumes out, or a sensor that has become faulty and is giving a false reading.
This fault can sometimes occur during period of high winds, as strong gusts can create back-pressure in the flue that interferes with the air pressure switch.
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.