Quick answer
A burning smell from your consumer unit at night is most likely caused by a loose or overloaded connection that heats up under sustained evening load — things like storage heaters, overnight appliances, or EV chargers drawing current for hours. This is a serious fire risk. Do not ignore it. Turn off the main switch at your consumer unit if the smell is strong, and call a qualified electrician as an emergency. Never assume a burning smell from electrical equipment will resolve on its own.
A burning smell coming from your consumer unit — your fuse box — is never something to dismiss, and the fact that it happens specifically at night gives us a useful clue about what is likely going on.
Why night-time matters
During the evening and overnight hours, certain appliances tend to run for long, continuous periods. Storage heaters, electric blankets, EV chargers, washing machines on economy cycles, and overnight freezers all place a sustained load on your circuits. If there is a loose connection, a deteriorating terminal, or an overloaded circuit anywhere in or near the consumer unit, prolonged current flow causes that fault to heat up far more than it would during short daytime use. Heat builds, insulation starts to scorch, and you notice the smell.
What you can safely check yourself
There is very little safe investigation you can do inside a consumer unit without proper training and equipment. However, you can do the following without opening anything:
1. Note exactly when the smell starts — is it linked to a specific appliance being switched on?
2. Check whether any circuit breakers feel warm to the touch on the outside of the unit cover.
3. Look at the area around the consumer unit for any discolouration on the wall or cover.
4. Check if the smell is also noticeable at any plug sockets or appliances running overnight.
Do not open the consumer unit cover. Do not ignore the smell and go to bed.
When to treat this as an emergency
If the smell is strong, acrid, or smells like melting plastic, turn off your main switch immediately and call an emergency electrician. If you see any scorch marks, smoke, or the smell makes you feel unwell, get everyone out of the property and call 999.
Even if the smell is faint, you should have a qualified electrician inspect the consumer unit within 24 to 48 hours at the most. This is not a job to put off. Loose connections in consumer units are one of the leading causes of domestic electrical fires in the UK, and they can ignite without further warning.
⚡ North London Electrician
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