Salter oven shows E4 and will not heat; sometimes appears after a power surge or lightning storm.

Safety first: Turn off power at the consumer unit or unplug the oven. Only qualified persons should test live voltages.

• Check supply: Verify that the oven is connected to the correct mains voltage specified on the Salter rating plate (typically 220–240 V AC). If lights in the home flicker or other appliances misbehave, have an electrician check the supply.
• Inspect mains terminal block: Remove the rear cover to access the mains terminal block. Tighten any loose screws and check for heat damage or melted plastic. Replace the terminal block if burnt.
• Examine mains filter / interference suppressor: Many Salter ovens use a small mains filter board or capacitor assembly. Look for bulging capacitors, burn marks, or cracked housings. Replace the mains filter assembly if damaged.
• Reset and retest: After tightening and inspecting, restore power and see if E4 clears. If the error persists and the supply is confirmed correct, the internal power supply on the main control PCB may be faulty and the PCB will need replacement.

Warning: Do not operate the oven with signs of overheating at the mains terminals. This can cause fire or electric shock.