Burning Smell from Consumer Unit: What to Do Safely

What should you do first if the consumer unit smells burnt?

If there is no smoke, flame or active sparking and you can safely reach the consumer unit, switch the main switch to the off position. Leave the installation switched off until the cause has been investigated.

Do not start operating individual breakers to find out which circuit is responsible. The smell may be coming from the main switch, a protective device, a connection, a cable or another part of the board, so repeated switching does not provide a safe way to diagnose the problem.

A burning smell at the consumer unit is an appropriate reason to seek an emergency electrician for burning smell, particularly where there is heat, discolouration, crackling, sparking or a rapidly worsening smell.

What can cause a burning smell from a consumer unit?

The smell usually indicates that an electrical component or connection has become hotter than it should. The exact source cannot be identified safely from smell alone, and several different faults can produce similar symptoms.

If crackling or arcing is part of the problem, the separate guide to electrical arcing warning signs explains that specific fault pattern in more detail.

What if the burning smell is only faint or occasional?

A faint or intermittent burning smell still needs attention. Electrical components can cool when demand reduces, which may make the smell disappear temporarily even though the underlying fault remains.

The fact that no breaker or RCD has tripped does not make the situation safe. A consumer unit showing signs of overheating, burning or unusual electrical smells should remain out of use until it has been checked.

If you can smell burning in the property but cannot confirm that it is coming from the consumer unit, the broader guide to a burning smell in the house with no visible smoke covers how to approach an unidentified source.

What should you not do with a burning consumer unit?

Keep the board closed and avoid attempts to repair or investigate it yourself. Internal consumer-unit work can expose live electrical parts and should not be treated as a visual DIY check.

• Do not remove the consumer-unit cover.
• Do not touch or tighten internal terminals.
• Do not repeatedly reset breakers, RCDs or RCBOs.
• Do not switch circuits on one by one to reproduce the smell.
• Do not spray water or other liquids onto electrical equipment.
• Do not assume the problem has cleared because the smell has faded.
• Do not continue using the installation simply because the lights and sockets still work.

Can you turn the main switch back on after the smell stops?

No. If you switched the main switch off because the consumer unit smelled burnt, leave it off until an electrician has established the cause and confirmed that the installation can be re-energised safely.

Switching the board back on to “test it” can put the damaged connection or component under load again. The absence of a smell while the electricity is off does not show that the original problem has been repaired.

What will an electrician check?

The inspection should focus on finding the source of the heat or burning rather than assuming the whole consumer unit automatically needs replacing.

Depending on what is found, the electrician may assess:

• the main switch and associated connections;
• circuit breakers, RCDs or RCBOs showing signs of heat damage;
• cable terminations and conductors within the affected area;
• discolouration, melting or damaged insulation;
• evidence of arcing or deteriorated connections;
• the circuit associated with any damaged protective device;
• the condition of the consumer unit after the immediate fault has been identified.

Heat damage does not automatically mean the complete board must be changed. If the inspection shows that wider replacement or upgrading is appropriate, a consumer unit assessment can establish the scope of the work rather than assuming replacement in advance.

What if the smell seems to come from one breaker?

Do not remove or handle the breaker to investigate it. Even if one protective device appears discoloured or smells stronger than the rest of the board, the cause may involve its connection, the circuit conductors or another part of the consumer unit.

If the board can be safely isolated using the main switch, leave it off. If the suspected device is actively sparking, smoking or producing enough heat to make approaching the board unsafe, move away from the consumer unit instead.

When should you leave the property and call 999?

Leave the property and call 999 if there is an actual fire, visible flame or smoke from the consumer unit. Do not remain inside trying to identify the damaged circuit or attempt to extinguish an electrical fire yourself.

Move away from the board rather than trying to reach the main switch if you see:

• smoke coming from the consumer unit;
• visible flames;
• active or repeated sparking;
• rapid melting or severe heat around the enclosure;
• a condition that makes approaching the consumer unit unsafe.