BoilerFaultCodes.com
HJ-08 Emergency

Your boiler has too much water pressure and needs some drained out to reach a safe operating level.

Technical description: High system pressure – the boiler needs to discharge water down to 0.8 bar
Typical repair cost: £0-120 (including labour)

DIY fix possible

Locate a radiator bleed valve and use a key to release water into a containerMonitor the boiler pressure gauge until it drops to between 1.0 and 1.5 barEnsure the filling loop valves are tightly closed so no more water enters the system

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A boiler cover plan would cover faults like HJ-08 — no call-out fees, no surprises.

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