Water heater does not start at all; no lights or display, completely dead.

Safety: Do not remove the heater's electrical cover unless you are competent with mains wiring. Always isolate power at the consumer unit first.

Steps:

• Check other appliances: Confirm that other electrical devices on the same circuit work. If not, reset the breaker or replace the fuse as appropriate.
• Inspect external switch: Ensure the fused spur or wall switch supplying the heater is turned on and that its fuse is intact (replace only with the specified rating).
• Check power indicator: If the heater has a power LED, verify whether it lights. If not, there may be an internal fuse or wiring fault that requires a technician.

Note: Internal electrical faults should be diagnosed and repaired by a qualified technician to avoid shock or fire hazards.