BoilerFaultCodesTechnical description
High Pressure Switch Operated
What causes this fault?
This fault occurs when the refrigerant pressure inside the heat pump exceeds safe working limits, causing the system to shut down to prevent damage. The most common reasons are a lack of water flow through the unit, often caused by a blocked filter, or a pump failing to move heat away from the system quickly enough.
This fault is more frequent during the first cold snaps of autumn or winter when the heat pump is required to work at its maximum capacity for the first time in months.
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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