BoilerFaultCodesYour main heat pump unit has lost communication with the secondary unit, meaning the system may not be able to provide full 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 Master Heat Pump to Slave Heat Pump Error
What causes this fault?
This fault occurs when the electrical signal used to share information between your two heat pump units is interrupted. The most common reasons are a loose or damaged connection cable between the units, or a malfunction in the electronic control boards that manage the system's communication.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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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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