A space heater making noise is, most of the time, doing one of four things its maker describes: switching the element on and off, running its fan, turning on its base, or, in an oil-filled radiator, heating up for the first time. De'Longhi, Dreo, Lasko, Vornado, Honeywell, Dyson and Dr. Infrared each explain some of these sounds, and no single maker explains them all.
Heater makers write much less about sound than refrigerator or dishwasher makers do. What follows comes from troubleshooting tables, FAQ answers and notes printed beside a feature, each quoted with the model it belongs to. Where no maker we read explains a sound, we say so instead of guessing.
A heater is a 1,500 watt appliance a few feet from furniture, so the signs that mean switch off and unplug matter more than any click. They are gathered in one list near the end of this page.
Is it normal for a space heater to make noise?
Yes, within limits the makers spell out. A fan heater makes a steady rush of air whenever it runs, and Dreo says on its Atom One page that "The higher the gear setting of the space heater, the louder the noise will be."
A heater's sound also changes through the evening, because its thermostat keeps moving it between high, low and off. Lasko's CT24362 manual says that in Auto Eco mode the tower drops to low heat when the room matches the set temperature, then shuts off once the room is "2 degrees above the set temperature". Each step is a new sound in a quiet room.
The quietest kind has no fan at all. Envi's FAQ says its wall panel warms a room "without a fan, dust, or noise", and De'Longhi, Dreo and Costway all sell oil-filled radiators that work by convection alone. Even those make some sound, as the crackling section below shows.
Why does my space heater click?
A space heater clicks mostly when its thermostat switches the element or fan, and some models also click as they oscillate or change airflow direction. Makers treat both as normal, with a few checks for clicks that come only while the heater turns.
Clicking as the thermostat cycles
De'Longhi uses the click as a setting aid. Its manual for two-switch oil-filled radiators says that once the room is warm, "turn the thermostat knob counter-clockwise very slowly and carefully until you hear a click." The radiator then holds the temperature "by cycling on and off as required."
De'Longhi's KH19 manual for its UK radiators gives the same instruction: turn the thermostat back until the light goes out or you hear a click, and no further. Neither manual says how loud later switching will be.
Fan heaters with an electronic thermostat switch in steps. Vornado's heater FAQ says that on its mechanical VH10, "When the room reaches set temperature, the heat and fan on the heater will shut off", then restart as the room cools. Its AVH10 "automatically adjusts (lowers) the heat element's wattage and fan speed" instead, which Vornado says "eliminates annoying hot and cold cycles."
Dr. Infrared describes a cycle that owners can mistake for a fault. Its DR-968 manual says that on standby the heater "will read the room temperature every 5 minutes by running the heating 40 seconds and fan 60 seconds." A heater that wakes for a minute in a warm room is taking a reading.
Clicking when it oscillates or changes airflow
Dyson calls one kind of click normal. On its Pure Hot+Cool support page, Dyson says that when the machine switches from front to rear airflow "there may be a clicking sound as the motor adjusts direction", which "is not an indicator of anything wrong with your machine."
For clicking that happens only during oscillation, Dyson's next step is to "Check around the base of the machine for any debris or obstructions", then remove and refit the filters. Dreo's Atom One FAQ says: "If there is cracking sound when oscillating, please try to apply lubricant to the base if possible."
Why does my space heater fan keep running after the heat stops?
A space heater's fan keeps running after the element switches off to clear heat from inside the unit. Lasko, Honeywell and Dr. Infrared all describe this run-on, which lasts from a few seconds to about a minute and a half.
Lasko's CT24362 manual says the tower "will continue to run for 15 seconds after the element has turned off." Honeywell's heater support page says that after you press the power button, "the unit will continue to blow air to cool down the internal components." Dr. Infrared's blower "will continue to run until the heat chambers cool down" and stops after 90 seconds.
Honeywell also accounts for a fan that keeps going once the room is warm: "once our heater fans reach the desired heat level or temperature selected the fan will continue to blow heated air." A fan that hums on after the element goes quiet is, by that account, part of the design.
Why is my space heater fan so loud?
Fan noise from a space heater rises with the setting, according to Dreo, which tells owners to turn the speed down first. If that does not help, Dreo asks for a stable surface and a short video so its support team can judge the sound.
Dreo's full list on the Atom One page reads: "Take a short video for us to confirm if it is abnormal", "Relocate the unit and ensure the heater is on a stable, secure surface" and "Try to apply lubricant to the base if the noise only happens while the heater rotates". No other heater maker we read is this specific about fan noise.
Dust changes how a fan heater runs. Lasko's manual says to "Vacuum intake grills every two weeks", and its troubleshooting list says a heater that "runs for several minutes and shuts off repeatedly" may "require cleaning". The same manual says "NEVER attempt to take apart the Heater."
Dyson's Pure Hot+Cool troubleshooter lists "Grating or grinding" and "Whining or whistling" among its noise types, and both choices lead to Dyson's telephone support page rather than to a fix you try at home.
Why is my space heater making a buzzing noise?
No heater maker we read explains a buzz in its own words. The nearest guidance covers the plug and wall outlet, which Vornado and Lasko both say must fit tightly and must never get hot, so a buzz you can trace to the plug falls under those warnings.
Vornado's Velocity Cube 5S guide says: "Check frequently during use to make sure plug and outlet are not hot. If so, discontinue using heater and have outlet replaced by a qualified electrician." Lasko's manual, in capitals, says to "BE SURE THAT HEATER PLUG FITS TIGHTLY INTO OUTLET BEFORE EACH USE."
Vornado also names the "signs of an electrical problem": "warm outlet coverplates, sparks when plugging in or operating, lights flickering/dimming during operation." Its instruction for any of them is "Immediately turn off and unplug the appliance", then have a qualified electrician look for the cause.
Both makers rule out the usual go-betweens. Lasko forbids plugging its heater into an extension cord, power strip, surge protector or "OUTLET-TYPE AIR FRESHENER", warning that such devices "MAY CREATE A FIRE HAZARD." Vornado's FAQ says its heaters "must never be used with extension cords, surge protectors, multi-outlet adapters, timers, or smart plugs."
If the plug and outlet stay cool and the hum comes from the fan, Dreo's fan advice above is the one that applies.
Why does my oil-filled radiator crackle?
An oil-filled radiator crackles or creaks mostly on its first run, and De'Longhi and Costway both call that normal in their manuals. De'Longhi's UK manual adds that the crackling can come back after the radiator has sat unused.
De'Longhi's US manual for its digital radiators says "Soft crackling sounds are normal during the heater's first operation." Its Dragon TRD40615E manual calls "creaking" on the first run completely normal and asks you to run the radiator at maximum power for at least two hours with the room well aired.
The KH19 manual extends the time frame: "It is normal for the heater to make 'crackling' noises during the first time it is switched on (or in the case of infrequent use)." Costway's ES10374US manual says "It is normal for the product to have a slight sound and odor during heating."
What about gurgling or dripping sounds?
Gurgling and dripping sounds from an oil-filled radiator are not described in any maker manual we read, so we cannot say whether a given maker counts them as normal. What the makers do cover is the oil itself, and their line is firm.
De'Longhi's KH19 manual says "The body of your radiator is filled with an exact quantity of oil", and that repairs "which call for the opening of the radiator" must be done "only by the manufacturer or an authorised service centre." Its US manual says "If you notice any leakage of oil, switch it off immediately and contact a service center". Costway says the same: "If leakage occurs, contact the after-sales service agent of the manufacturer."
For choosing a radiator by what its maker says about sound, see our quietest oil-filled radiators guide.
Does the tip-over switch make a rattle or click?
No maker we read describes any sound from a tip-over switch. Lasko, Vornado, Honeywell and Dr. Infrared describe only what the switch does: it cuts power when the heater tips, and the heater runs again once it stands upright.
Vornado's guide puts it in one line: "If heater tips over, safety shut-off system cuts power to heater. Position heater back in upright position and power is restored." Dr. Infrared asks for "a flat, smooth, stable surface to prevent the heater from tipping over again", and Honeywell says not to use a heater on "bedding or deep carpeting."
Honeywell explains a heater that beeps and stops heating: "Your tip over switch has been activated. Right the tipped over heater and turn the unit On." If the display shows E1, Honeywell says "there is a malfunction with the tip-over switch on the unit. You will no longer be able to operate your unit", and owners should contact its Consumer Relations department.
None of these makers offers a way to get around the switch, and neither do we. A heater that keeps cutting out while it stands on a hard, level floor is one for the maker's customer service.
When the overheat cut-out stops it
The overheat cut-out is the other switch that can silence a heater without warning. Lasko says that once "an overheat temperature is reached, the Heater will automatically shut off", and the only reset it gives is to unplug the heater, wait 10 minutes for it to cool, and plug it back in.
Vornado says that if its safety shut-off "repeatedly shuts off your heater or if it will not reset", owners should call its Consumer Services Department. De'Longhi's Dragon manual is shorter still: "A safety device switches the heater off in the event of overheating. Please call the De Longhi customer service."
Why does my space heater smell like burning?
A new space heater often smells for its first few hours of use, and Dr. Infrared, Dreo, De'Longhi and Envi each describe that smell as expected. In an older fan heater, Vornado links odors to dust, hair and debris collected inside.
Dr. Infrared's manual says "There may be a trace of smoke or odor when the unit is first operated", explaining that "a drop of oil fell on the interior coils during the manufacturing process" and that it "should not recur." Dreo's FAQ on its Radiator 521 page says new machines have "a slight odor" and suggests using them "with ventilation for the first few uses".
Envi calls a mild "new heater" scent normal for the first 48 to 72 hours and suggests running the panel at its highest temperature to clear it. De'Longhi's two hours at maximum power on the Dragon serve the same purpose.
For a heater past its first week, Vornado says that "Keeping the heater clean from dust, hair and debris can also help eliminate unwanted odors caused by accumulation of these particles inside the unit." It recommends vacuuming the grilles and periodically blowing the heater out with pressurized air, with the heater unplugged.
No maker we read sets a rule for when a smell stops being normal. They do share one instruction: Lasko, Vornado and Dr. Infrared all say not to operate a heater "after the heater malfunctions, has been dropped, or damaged in any manner", in Dr. Infrared's words, and to return it for service.
Why does my space heater pop the breaker?
A space heater pops the breaker when it pulls more current than the circuit can carry alongside everything else on it, according to Dreo, Vornado and Honeywell. Dreo adds that a heater with an internal short should be replaced.
Dreo's answer reads: "The power exceeds the home circuit load. Please unplug other high power appliances and try again", followed by "If it is tripping due to product short circuit, replacement should be arranged". Honeywell notes that more than one heater on the same circuit "could trip the circuit breaker and shut the unit and other appliances connected on that circuit."
Vornado suggests running the heater on its "low" setting, "only running one heater at once" and unplugging other electrical products, or hiring an electrician to add a circuit. Its troubleshooting table also warns that ground fault outlets "may cause nuisance tripping" and says to move the heater to "a standard wall outlet."
Which space heater sounds mean you should unplug it?
Sparks, a hot plug or outlet, flickering lights, a grinding fan, leaking oil and repeated safety shut-offs are the signs the makers tie to stopping and calling for help. Each item below is the maker's own instruction.
- A plug or outlet that feels hot: Vornado says stop using the heater and have an electrician replace the outlet.
- Sparks, warm outlet coverplates or lights that flicker or dim while it runs: Vornado says turn it off and unplug it immediately.
- Grating, grinding, whining or whistling from a Dyson heater: Dyson's troubleshooter sends you to telephone support.
- Oil on the floor under a radiator: De'Longhi says switch it off immediately and contact a service center.
- A dropped, damaged or faulty heater: Lasko, Vornado and Dr. Infrared say do not operate it.
- An overheat cut-out that keeps tripping or will not reset: Vornado and De'Longhi say call their service lines.
- An E1 code on a Honeywell heater: Honeywell says the tip-over switch has failed and to contact Consumer Relations.
De'Longhi's US manual closes the subject: "In case of malfunction or doubt, do not try to repair the heater by yourself: it may result in fire hazard or electric shock." Its Dragon manual says "Do not open the appliance. No user-serviceable parts inside."
How loud is a normal space heater?
A normal fan space heater is rated somewhere in the mid 20s to mid 40s in decibels by the few makers that publish a figure. Where a maker names the setting, the low number is the quietest one, and no maker of a portable heater gives a measuring distance.
Dreo lists 25 dB for its Whole-Room Heater 720, and its heater series page footnotes that figure as "Tested at the lowest airflow heat setting." Dyson rates the Hot+Cool HF1 at 26 dBA in Quiet Mode and 44 dBA at maximum, the only heater we found with both ends published. Our quietest space heaters guide compares these and others.
Lasko prints "Noise dB-Low" and "Noise dB-High" rows on some product pages without naming the setting; the CT24362 tower shows 37 dBa and 44 dBa. Every Lasko figure is listed on our Lasko space heater decibels page, and Dreo's on the Dreo space heater decibels page.
For radiators, the only figure we found is Costway's statement that its 700 watt mini radiator "is lower than 45 db", an upper limit with no test conditions. To place these numbers against everyday sounds, see the decibel chart and our note on dBA.
Do space heater makers publish decibel ratings?
Yes, but seldom with test conditions. Of the 49 heaters in our catalog on the day we counted, October 26, 2026, 31 print a decibel figure above zero, 13 print none, and 5 fanless models claim silence or 0 dB.
The count draws on the fact sheets behind our space heater, radiator and garage heater guides, each quoting the maker's product page, spec table or manual. It covers only the heaters we track. An upper limit counts as a figure, such as Lasko's "less than 40 dB" for the Ellipse 12 tabletop heater.
Distance appears only on garage unit heaters. Modine's two Amp Dawg sizes and its Hot Dawg HD30, and Reznor's UDXC 60 and EUHC 5, give figures at 5, 10 or 15 feet. Modine's data sheet adds that the values should only compare similar equipment "at the same distance and in the same environment." No portable heater in the catalog names a distance.
Dreo says more than most about its test setting. Six Dreo heaters carry a footnote tying the figure to their quietest heat or fan level; the Whole-Room Heater 725's 25 dB is one. Three other Dreo pages print conflicting figures for one model: the Solaris Slim H3 page shows 40, 37.5 and 34 dB in different places.
The 0 dB claims belong to heaters with no fan: Envi's two wall panels, Dreo's 711S convection heater and Radiator 521, and Heat Storm's Tradesman. Zero decibels is the threshold of hearing, so we read those as claims of silence, not measurements, and never rank them against a measured figure.
How did we put this together?
QuietSpecs built this space heater page from maker documents only. We used De'Longhi's US and UK oil-filled radiator manuals, including the Dragon TRD40615E; Costway's ES10374US manual; Dreo's FAQs on its Atom One and Radiator 521 pages; Lasko's CT24362 manual; Vornado's FAQ and Velocity Cube 5S guide; Honeywell's heater support page; Dr. Infrared's DR-968 manual; Dyson's Pure Hot+Cool troubleshooter; and Envi's FAQ.
We did not plug in, listen to, open or repair any space heater or radiator for this page. Pelonis publishes its HO-0279 manual only as images, so we could not quote it. Where a sound is missing from every document above, the page says so rather than offering a cause of our own.
