Gledhill water heater completely dead, no lights or display

Safety: Only work on electrical circuits if you are competent. Always isolate at the consumer unit before removing covers.

Steps:

• Check supply: Verify that other electrical devices on the same circuit work. Check the MCB or RCD at the consumer unit and reset if tripped.
• Fused spur: Inspect and replace the fuse in the local isolator with the correct rating if blown. If it blows again immediately, there is a fault that needs investigation.
• Terminal check: With power off, remove the fused spur and cylinder terminal cover to check that live, neutral, and earth are securely connected.
• PCB power: If supply is present at the PCB but there are no signs of life (no LEDs, no display), the PCB’s power supply section may have failed and the board will need replacement.

Note: Repeated fuse or breaker trips indicate a short circuit or earth fault; do not keep resetting without finding the cause.