BoilerFaultCodesTechnical description
High Pressure Switch Operated
What causes this fault?
This fault occurs when the internal pressure of the refrigerant or the water system exceeds safe operating limits, triggering a safety switch to protect the unit. The most common reasons are a lack of water flow through the heat pump caused by a blocked filter or a failing circulation pump, which prevents heat from being transferred away quickly enough.
This fault is more common during the first cold snaps of autumn or winter when the system is under higher load after being idle during the summer 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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