BoilerFaultCodesYour indoor control panel has lost communication with the outdoor unit, meaning your heat pump cannot receive instructions to provide heating or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: No connection Outdoor PCB to User Interface
What causes this fault?
This fault occurs when the digital bridge between your indoor controls and the outdoor unit is broken, preventing them from talking to each other. The most common reasons are a loose or damaged connection cable, a blown fuse, or a technical failure within one of the main circuit boards.
This fault can occasionally occur after heavy storms or high winds if debris or moisture has compromised the external wiring connections.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E2 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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