BoilerFaultCodesTechnical description
Neon indicators for Central Heating and Hot Water (0 to 4 bar gauge reference)
What causes this fault?
This fault occurs when the boiler's internal sensors detect that the water temperature has risen too quickly or exceeded safe limits. The most common reason is a lack of water circulation, often caused by a failing pump or a blockage in the system preventing heat from being moved away from the burner.
This issue frequently appears during the first cold spell of autumn when the pump may have seized after being inactive throughout the summer.
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.
Find a Gas Safe engineer
Search the official register →