BoilerFaultCodesTechnical description
Condensing Temperature High
What causes this fault?
This fault occurs when the water temperature within the heat exchanger rises too quickly or exceeds safe limits, causing the boiler to shut down to prevent damage. The most common reason is a lack of water flow, often caused by a failing pump or a blockage in the system pipes that prevents heat from being carried away from the unit.
This fault is frequently seen at the start of autumn when heating systems are turned back on after a summer of inactivity, which can cause internal pump components to seize.
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.
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