Electric Heater Smells Like Burning? Dust, Plug or Wiring

By Ray Bennett · Updated 2 October 2026 · 10 min read · Checked against the sources at the end

Electric Heater Smells Like Burning? Dust, Plug or Wiring

Short answer

A burning smell the first time an electric heater runs, or after it has sat unused, is usually factory oil or dust burning off the element, and Cadet, Dimplex, King and Stelpro say it fades. If it keeps coming back, turn the power off, let it cool and clean the dust out. A hot plug or outlet, warm outlet covers or sparks mean stop using it and call an electrician.

A burning smell from an electric heater the first time it runs, or the first time each fall, is usually factory oil or dust burning off the element, and Cadet, Dimplex, King and Stelpro say that fades. A smell that keeps coming back, or one from the plug, the outlet or the wall, points somewhere else, and some of those mean switch it off now.

Dimplex notes that its electric heaters burn no fuel and give off no combustion exhaust or gases, so the smell is not gas or exhaust from the heater itself.

Before you start

What to carry: a torch and a vacuum cleaner with a brush attachment, plus a hair dryer for a wall heater.

Gas or electric? This page is about electric heaters: plug-in space heaters, electric baseboard heaters and electric wall heaters. A gas or oil furnace that smells like burning is covered in a furnace that smells, and a heat pump in a heat pump that smells.

Three rules before you go looking. Warm outlets or sparks: off now. Vornado says never to ignore warm outlet cover plates, sparks when plugging in or running, or lights that flicker or dim: turn the heater off and unplug it at once, and have an electrician find the cause before it is used again. NFPA says to call a qualified electrician or your landlord for a burning or rubbery smell from an appliance.

Power off and cool before you clean. Vornado and Honeywell say to unplug a space heater before cleaning it, and De’Longhi says to wait for it to cool too. For a baseboard or wall heater, Cadet and Stelpro say to turn the power off at the breaker and let the heater cool first. Cadet and King warn that breakers are often not marked correctly, so make sure the heater is really off before a cover or grill comes off.

Straight into the wall. CPSC says to always plug an electric space heater directly into a wall outlet and never into an extension cord or power strip, to prevent overloading and a fire. Vornado and Honeywell’s HCE200 manual say the same.

Which burning smell is it

What a burning smell from an electric heater usually means, from the makers' manuals, CPSC and NFPA. Start with check 1 below.

Check 1Normal, it fades

A new heater, or the first run after a rest

A new heater. Cadet says to run a newly installed heater on its highest setting for 30 minutes, and that some smoking may occur as the element burns off residue from manufacturing. Cadet and Dimplex say that odor typically goes away within several hours. King says to let a new system run steadily for half an hour, and that burning off light finishing oil is normal: open windows and let the room air out until it stops, usually within a few minutes.

An oil-filled radiator. De’Longhi says to run a new one at maximum power for at least two hours the first time, with the room well ventilated, to get rid of the new smell.

The first cold day. Stelpro’s baseboard guides say it is normal for the heater to give off some temporary odors and whitish smoke when started for the first time or after a long period. Dimplex says a mild odor at first use or after a long period unused comes from dust or protective coatings burning off.

When it does not fade. Dimplex says that if the smell persists, disconnect the power and clean the heater thoroughly, and for a new heater whose smell persists, disconnect the power and contact its support.

Check 2

A space heater: clean the dust out

Why. Vornado says dust, hair and debris build up inside a heater as it moves air, and blowing it out keeps the element and motor clear and gets rid of the odors those particles cause.

Vornado’s steps. Unplug the heater. Vacuum the dust off the front outlet grille and the air inlets on the sides with the brush attachment of a household vacuum cleaner, then wipe the whole heater with a soft, dry cloth. Vornado says to periodically blow the heater out with pressurized air as well.

How often. Vornado recommends cleaning the outside weekly, and Honeywell’s manuals say at least once a month and before storage. Vornado says to store a heater covered, or in its box, so it does not collect dust.

An oil-filled radiator. De’Longhi says to unplug it and wait for it to cool, then remove the dust with a soft, dry cloth. On models with a turbo heating fan, a safety device switches the radiator off if dust builds up on the air intake and output grills: unplug it, let it cool and vacuum the grills before turning it back on. For its overheating safety device, De’Longhi says to contact an authorized service centre to reset it.

Check 3

A baseboard or wall heater: clean the dust out

A baseboard heater. Stelpro says a slight burning smell when heaters come on in autumn is one sign they need maintenance, and to clean a baseboard at least once a year. Turn the power off at the breaker, let the element cool, take the front cover off gently and vacuum the fins with the small round brush of a vacuum cleaner without bending them. King warns the fins are sharp and may cause cuts. Ouellet says never to remove the grill on its heaters: vacuum the front of the grill instead.

A wall heater: check for a recall first. Some Cadet and Encore in-wall heaters have been recalled for smoking, sparking and fire: the Cadet recalls to check.

Cadet’s steps. Cadet says to clean its wall heaters at least every six months. Turn off the power at the main disconnect panel, make sure it is really off, and wait for the heater to cool. Remove the grill, wash it in hot soapy water and dry it. Blow air through the element with a hair dryer or a shop vacuum on blow, vacuum the fan without touching the element, put the grill back and turn the power on.

Lock the panel. Cadet’s Com-Pak guide says to lock or tag the panel door so nobody turns the power back on while you work. Cadet says any service other than cleaning should be done by an authorized service representative.

On a Marley. Marley says owners should only vacuum and wipe the outside and the grille openings of its Smart Series wall heater once it has cooled. Taking the grille and heater assembly out is for a qualified service person, at least once a year.

Check 4Free to check, an electrician for the outlet

A hot plug or outlet: feel them

A warm plug is normal; a hot plug or a warm outlet is not. Honeywell says it is normal for its heater’s plug to feel warm, but a loose fit between the outlet and the plug may cause overheating and distortion of the plug, and a qualified electrician should replace a loose or worn outlet.

FEEL THE PLUG AND THE OUTLET

Plug warm to the touch normal, Honeywell says Plug or outlet hot a loose outlet: stop, call an electrician Plug bent out of shape a damaged plug: do not run the heater Warm cover plate, sparks, lights dimming Vornado: turn it off and unplug it now Straight into the wall no extension cord or power strip NFPA: only one heat-producing appliance in an outlet at a time.

A warm plug is normal. A hot plug or outlet, a warm cover plate or sparks mean stop using the heater, Vornado says, and Honeywell says a loose outlet can overheat and distort the plug.

Vornado’s check. Vornado says a loose fitting outlet can make the plug overheat or cause a fire, so check often while the heater runs that the plug and outlet are not hot. If they are, stop using the heater and have the outlet replaced by a qualified electrician. Vornado adds that a heater draws more current than small appliances, so an outlet can overheat with a heater even if it has not with other appliances.

A bent or damaged plug. Honeywell and Vornado say never to run a heater with a damaged cord or plug, or after it has malfunctioned or been dropped or damaged. A plug that has lost its shape counts.

Aluminum wiring. Honeywell says that if your home has aluminum wiring, a licensed electrician should check the outlet’s connections, because aluminum wire connections can cause a safety issue with a 1500 watt heater.

One heater per outlet. NFPA and ESFI say to plug only one heat-producing appliance into an outlet at a time. ESFI lists a burning odor from outlets or wall switches, and warm or discolored wall plates, among the warning signs of an overloaded circuit.

Check 5

Look for anything touching or too close

Space heaters. CPSC says portable heaters can cause fires if they are too close to things that burn, such as drapes, furniture or bedding, so keep them at least three feet away. Vornado’s list adds pillows, papers, clothes, curtains and electrical outlets, and says not to put a heater near a bed, where pillows or blankets can fall onto it. Vornado also says never to let anything get into its heater’s openings, as it may cause a shock or fire.

Oil-filled radiators. De’Longhi says never to cover the radiator while it runs, never to use it to dry damp clothes, and never to rest the cord on its hot elements.

Baseboard and wall heaters. The makers give their own clearances: see a baseboard heater not working and an electric wall heater not working.

A smell that means the wiring

A wired heater that smokes or smells burnt. Cadet’s chart for a wall heater that discharges smoke or gives off a burnt odor lists dust or lint inside, and poor or loose electrical connections. For the connections, Cadet says to turn the power off at the breaker and not to turn it back on until every connection has been checked and repaired. Have an electrician do that check.

Glowing red or shutting itself off. Cadet and Dimplex say a heater that glows red, or keeps getting unusually hot and shutting off, shows signs of overheating: turn its breaker off immediately. Marley says not to keep using its wall heater if it repeatedly cycles off on its thermal limit, and if nothing blocks it, to have it inspected by a reputable electrician or repair service.

A hot insulation smell. ESFI lists an odor of hot insulation, and switch plates or outlet covers that are hot or discolored, among the signs of a wiring hazard, and says to have a licensed electrician inspect the wiring.

A recalled heater. CPSC says to check www.cpsc.gov/recalls, and if a product is recalled, stop using it right away and contact the company for the remedy. For the old Cadet and Encore in-wall models, CPSC lists no remedy now and says they stay a fire hazard until they are replaced.

What each one costs

The step	Cost
New heater smell, aired out	Nothing
Cleaning a space heater	Nothing
Cleaning a baseboard or wall heater	Nothing
A loose or worn outlet replaced	An electrician
Loose wiring connections	An electrician
A recalled heater	Apex72: a free new heater, installed. Old Cadet and Encore: CPSC lists no remedy now

Questions people ask

Is it normal for an electric heater to smell like burning?

At first, yes. Cadet and King say a new heater burns off factory residue or oil. Stelpro says some odor and whitish smoke at first start or after a long period is normal, and Dimplex says a heater that has not run for a long time burns off dust. If the smell persists, Dimplex says to disconnect the power and clean the heater.

Why does my space heater smell like burning plastic?

Feel the plug and the outlet. Honeywell and Vornado say a loose outlet can overheat the plug, and Honeywell says it can distort it. Vornado says to stop using the heater and have an electrician replace the outlet. If the smell comes from the heater itself, stop using it: NFPA says to call a qualified electrician for a burning or rubbery smell from an appliance.

Why does my baseboard heater smell like burning?

Usually dust on the element, most of all on the first cold day. Stelpro says to turn the power off, let it cool and vacuum the fins at least once a year. If the smell persists after cleaning, Dimplex says to disconnect the power and contact the maker’s support.

How long does a new heater smell last?

Cadet and Dimplex say the odor typically goes away within several hours, and King says usually within a few minutes with the windows open. De’Longhi says to run a new oil-filled radiator at full power for at least two hours with the room ventilated.

When is a burning smell from a heater dangerous?

When it comes with a hot plug or outlet, warm cover plates, sparks or flickering lights, when it is rubbery, or when the heater glows red. Vornado says to turn the heater off and unplug it, and Vornado and NFPA say to call a qualified electrician.

The other electric heat guides: a space heater not working, a space heater making noise, a baseboard heater making noise and an electric wall heater not working.

Sources: Cadet Energy Plus owner's guide, Com-Pak and Com-Pak Twin owner's guide and baseboard owner's guide 720001, Dimplex heater FAQ and T Series owner's guide, Stelpro "Maintenance of your heating units" and ABA and SBB baseboard user's guides, King K Series baseboard and WHF wall heater instructions, Marley Smart Series wall heater instructions 5200-11074, Ouellet FAQ, Vornado MVH and Honeywell HCE200 and HZ-0360 space heater manuals, De'Longhi oil-filled radiator instructions, CPSC release 25-101 (January 2025), CPSC recalls 00-070 (Cadet and Encore in-wall heaters, 2000) and 24-360 (Cadet Apex72, 2024), NFPA electrical safety tips, and ESFI home wiring safety tips and "Don't Overload Your Home"