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Kitchen extraction cleaning - fan tripping
An extract fan that trips out - cutting off its protection - when it's working hard is telling you something is wrong. Usually it's drawing too much current, often because a grease-laden fan is straining and overheating. Tripping is the protection doing its job, and a warning to act. Here is why your fan trips out under load, and what to do. This is general guidance, not electrical advice.
The short answer
An extract fan that keeps tripping out when it's under load - working hard - is a real warning sign. The trip is a protection cutting the fan off, and it's doing so for a reason. Here's why your fan trips out under load, and what to do. This is general guidance, not electrical advice; electrical faults are for a qualified person. What tripping under load means. When your fan trips out under load, it cuts off - via its overload or thermal protection, or its circuit breaker - when it's working hard. This usually means the fan is drawing too much current, and the protection is responding: cutting the fan off to prevent it drawing excess current and overheating (which could damage or burn out the motor). So the trip isn't random - it's the protection doing its job, telling you the fan is drawing more than it should. The usual cause: grease strain. The commonest reason a fan draws too much current and trips is grease strain. As grease builds up on the fan blades and housing, it loads and unbalances the fan, so the motor has to work harder to turn it - drawing more current and running hotter. And grease in the wider system (filters, ductwork) raises the airflow resistance, so the fan strains harder still. If the fan is strained enough (heavily grease-laden, fighting a choked system), it can draw excess current and overheat - tripping its overload or thermal protection, which cuts it off to protect the motor from burning out. So a fan tripping out under load is usually the protection responding to a grease-strained, overheating fan (as covered in the why-does-an-extractor-fan-keep-tripping page). It's a clear warning that the fan is under too much strain. Other possible causes. Grease strain is the usual culprit, but not the only cause. Others include: a worn or failing fan motor - worn bearings or a failing motor drawing excess current (often itself the result of prolonged grease strain); a seizing fan - a fan grease-seized or mechanically stuck, drawing a large current as it struggles or stalls (as covered in the cost-of-an-extract-fan-seized-by-grease page); or an electrical fault - a fault in the fan or its supply, which is a matter for a qualified electrician. So while grease strain (and the wear it causes) is the usual cause, especially alongside a greasy system, the fan motor may be worn or there may be an electrical fault - which a check would identify. Don't just keep resetting it. Whatever the cause, don't just keep resetting the trip and carrying on. The trip is a protection working - cutting off a fan that's drawing too much and overheating - so repeatedly resetting it forces a straining, overheating fan to keep running, risking motor damage or burnout (and defeating the protection that's trying to prevent that). So a tripping fan needs the cause addressed, not the trip repeatedly overridden. What to do. The response is to get the extraction cleaned and the fan checked. Cleaned: a proper extraction clean removes the grease that's loading and unbalancing the fan and choking the system - so the fan runs normally again, drawing normal current and not overheating (removing the usual cause of the tripping). Checked: the fan's condition is checked - in case the grease strain has worn or damaged the motor (which cleaning won't fix), or the fan is seizing. And if tripping persists after cleaning: because tripping involves the fan's electrical protection, a persistent trip should be checked by a qualified electrician or engineer (it may be a worn motor or an electrical fault). So the sequence is: clean the system (removing the grease strain, the usual cause), check the fan, and if it still trips, get it investigated electrically. The takeaway. So a fan tripping out under load usually means it's drawing too much current - most often because a grease-laden fan is straining and overheating - and the trip is the protection working, a warning to act. Get the extraction cleaned (to remove the strain) and the fan checked (for wear), and don't just keep resetting the trip. So heed the trip - it's protecting a straining fan. This is general guidance, not electrical advice.
Key points
What tripping means
When your extract fan trips out under load, it cuts off - via its overload or thermal protection, or its circuit breaker - when it's working hard. This usually means the fan is drawing too much current, and the protection is responding by cutting the fan off to prevent it drawing excess current and overheating (which could damage or burn out the motor). So the trip is the protection doing its job.
This matters because it means the trip isn't random or a nuisance to be overridden - it's a signal that the fan is drawing more current than it should, and the protection is stepping in. A fan running normally draws its normal current and doesn't trip; a fan tripping out under load is drawing excess current (usually because it's straining, covered next). So the trip is telling you something is wrong with how the fan is running. Understanding this is the key to responding correctly: the trip is a warning of an over-drawing fan, not just an inconvenience. So what tripping means - the fan is drawing too much current - is the starting point: the trip signals an over-drawing, protection-tripping fan, which has a cause worth finding (usually grease strain). So the trip means the fan is drawing excess current. This is general guidance, not electrical advice.
Usually grease strain
The commonest reason a fan draws too much current and trips is grease strain. As grease builds up on the fan blades and housing, it loads and unbalances the fan, so the motor has to work harder to turn it - drawing more current and running hotter. And grease in the wider system (filters, ductwork) raises the airflow resistance, so the fan strains harder still against a more choked system. So a grease-laden fan works harder, draws more current, and runs hotter than a clean one.
If the fan is strained enough - heavily grease-laden and fighting a choked system - it can draw excess current and overheat, tripping its overload or thermal protection (which cuts it off to protect the motor from burning out). So a fan tripping out under load is usually the protection responding to a grease-strained, overheating fan (as covered in the why-does-an-extractor-fan-keep-tripping page). The 'under load' part fits: the fan draws most current (and strains most) when working hardest, so a grease-strained fan is most likely to trip when under load. So usually grease strain - a loaded fan draws more and overheats - is the main cause: the grease loads and unbalances the fan, making it draw excess current and overheat until the protection trips. This is a clear warning of a badly grease-laden, strained fan. So grease strain usually makes the fan over-draw and trip. This is general guidance, not electrical advice.
Other possible causes
Grease strain is the usual culprit, but not the only cause of a fan tripping under load. Other possibilities: a worn or failing fan motor - worn bearings or a failing motor drawing excess current (often itself the result of prolonged grease strain, so grease and wear are linked). A seizing fan - a fan grease-seized or mechanically stuck, drawing a large current as it struggles or stalls (a severe case, as covered in the cost-of-an-extract-fan-seized-by-grease page). Or an electrical fault - a fault in the fan or its electrical supply, which is a matter for a qualified electrician.
So while grease strain (and the wear it causes) is the usual cause - especially alongside a visibly greasy system - the fan motor may be worn, the fan may be seizing, or there may be an electrical fault. These need identifying: cleaning addresses the grease strain, but a worn motor needs repair/replacement, a seizing fan needs freeing or replacing, and an electrical fault needs an electrician. Often they're linked (grease strain having worn or seized the fan), so cleaning plus a check covers most cases, with electrical investigation for a persistent trip. So other possible causes - a worn motor, a seizing fan, or a fault - mean a tripping fan isn't always purely grease; the fan may be worn or faulty, which a check (and, for a persistent electrical trip, an electrician) would find. So consider fan wear, seizing, and electrical faults too. This is general guidance, not electrical advice.
Don't just reset it
Whatever the cause, don't just keep resetting the trip and carrying on. The trip is a protection working - cutting off a fan that's drawing too much current and overheating - so repeatedly resetting it forces a straining, overheating fan to keep running, risking motor damage or burnout (and defeating the protection that's trying to prevent exactly that). So resetting and ignoring is the wrong response.
It's tempting, when a fan trips, to just reset it and keep going (the extraction is needed, and resetting seems easier than investigating). But this is counterproductive and risky: the fan is tripping because it's drawing too much and overheating, so forcing it to keep running (by repeatedly resetting) subjects the motor to the very stress the trip is protecting against - potentially damaging or burning out the motor (turning a cleanable grease-strain problem into a fan replacement). So the trip should be treated as a warning to address the cause, not an obstacle to override. So don't just reset it - the trip is protecting the fan - is an important caution: repeatedly resetting a tripping fan risks destroying it, so address the cause (clean and check) rather than overriding the protection. So don't keep resetting; address why it's tripping. This is general guidance, not electrical advice.
Clean it and check it
The response to a fan tripping out under load is to get the extraction cleaned and the fan checked. Cleaned: a proper extraction clean removes the grease that's loading and unbalancing the fan and choking the system - so the fan runs normally again, drawing normal current and not overheating (removing the usual cause of the tripping). So cleaning addresses the commonest cause. Checked: the fan's condition is checked - in case the grease strain has worn or damaged the motor (which cleaning won't fix), or the fan is seizing.
And if tripping persists after cleaning: because tripping involves the fan's electrical protection, a persistent trip should be checked by a qualified electrician or engineer (it may be a worn motor drawing excess current, a seizing fan, or an electrical fault). So the sequence is: clean the system (removing the grease strain, the usual cause), check the fan (for wear or seizing), and if it still trips, get it investigated electrically. This addresses the tripping properly - removing the strain, catching any wear, and identifying any electrical fault - rather than just repeatedly resetting a failing fan. So clean it and check it - remove the strain, check for wear - is the takeaway: a tripping fan is a warning of a strained, usually grease-laden fan, so clean the grease away, check the fan, and get a persistent trip investigated - don't just keep resetting it. So heed the trip and address the cause. This is general guidance, not electrical advice.
Questions
Usually because it's drawing too much current - most often a grease-laden fan straining and overheating - so its overload or thermal protection cuts it off; the trip is the protection responding to an over-drawing fan. An extract fan tripping out under load usually means it's drawing too much current, so its protection (overload or thermal protection, or the breaker) cuts it off to prevent damage. The commonest reason is grease strain: as grease builds up on the fan, it loads and unbalances it, so the motor works harder - drawing more current and running hotter; grease in the wider system raises the airflow resistance, straining the fan further. If strained enough, the fan draws excess current and overheats, tripping its protection (which cuts it off to save the motor from burning out). So the trip is the protection responding to a grease-strained, overheating fan - most likely to trip 'under load' because the fan draws most current when working hardest. Other causes (a worn motor, a seizing fan, an electrical fault) are possible, but grease strain is usual. So clean the system and check the fan, don't just reset it. So usually a grease-strained fan drawing too much current. So a grease-laden fan straining and over-drawing. This is general guidance, not electrical advice.
Yes - the trip is the protection cutting off a fan drawing too much current and overheating, so it's warning you the fan is under too much strain (usually grease); heed it by cleaning and checking, not by repeatedly resetting. Yes - a tripping fan is a clear warning sign. The trip is a protection working: it cuts off the fan because the fan is drawing too much current and overheating (which could damage or burn out the motor). So the trip is telling you the fan is under too much strain - most often because it's grease-laden (loaded and unbalanced, fighting a choked system) and drawing excess current. So it's a warning that the fan is straining beyond what it should, on a path toward motor damage or failure if not addressed. The right response is to heed the warning: get the extraction cleaned (to remove the grease strain, the usual cause) and the fan checked (for any wear the strain has caused), rather than just repeatedly resetting the trip (which forces the straining, overheating fan to keep running and risks burning out the motor). So a tripping fan is a warning to act on, not a nuisance to override. So yes - it's the protection warning of a strained fan. So yes; heed it and address the cause. This is general guidance, not electrical advice.
No - the trip is protecting a fan that's over-drawing and overheating, so repeatedly resetting forces it to keep running under that stress, risking motor damage or burnout; address the cause (clean and check) instead. No - you shouldn't just keep resetting the fan when it trips. The trip is a protection working - cutting off a fan that's drawing too much current and overheating, to protect the motor. So repeatedly resetting it forces the straining, overheating fan to keep running, subjecting the motor to the very stress the trip is protecting against - risking motor damage or burnout. So resetting and carrying on is counterproductive and risky: it can turn a cleanable grease-strain problem into a burnt-out fan needing replacement, and it defeats the protection that's trying to prevent that. So instead of overriding the trip, address why it's tripping: get the extraction cleaned (removing the grease strain, the usual cause), the fan checked (for wear or seizing), and, if it still trips after cleaning, investigated by a qualified electrician or engineer. So don't keep resetting it - address the cause. So no - resetting risks destroying the fan. So no; fix the cause instead. This is general guidance, not electrical advice.
Often yes, if the cause is grease strain - cleaning removes the grease loading and straining the fan, so it draws normal current and stops overheating; but if the motor is worn or there's an electrical fault, it may still trip and need a repair or an electrician. Often yes - if the tripping is caused by grease strain (the commonest cause), cleaning will usually stop it. A proper extraction clean removes the grease that's loading and unbalancing the fan and choking the system - so the fan runs normally again, drawing normal current and not overheating, and therefore not tripping its protection. So cleaning addresses the usual cause. However, cleaning won't fix the tripping if the cause is something the grease strain has left behind or a separate fault: a worn or damaged motor (from prolonged strain) may still draw excess current and trip even after cleaning; a seizing fan may need freeing or replacing; and an electrical fault needs an electrician. So the approach is to clean the system (removing the grease strain), check the fan (for wear or seizing), and if it still trips after cleaning, have it investigated by a qualified electrician or engineer. So cleaning stops grease-strain tripping, but a worn fan or fault needs more. So often yes for grease; otherwise a repair. This is general guidance, not electrical advice.
Then it's likely a worn or failing motor, a seizing fan, or an electrical fault rather than grease - which needs the fan inspected and repaired, and a persistent electrical trip investigated by a qualified electrician or engineer. If the fan still trips after a proper clean, the cause is probably not grease strain but the fan itself or an electrical issue. Possibilities: a worn or failing motor (worn bearings or a failing motor drawing excess current - often the result of prolonged grease strain before cleaning); a seizing fan (grease-seized or mechanically stuck, drawing a large current); or an electrical fault (in the fan or its supply). These need identifying and fixing: a worn motor needs repair or replacement, a seizing fan needs freeing or replacing, and an electrical fault needs a qualified electrician. Because tripping involves the fan's electrical protection, a persistent trip after cleaning should be checked by a qualified electrician or engineer, who can determine whether it's a mechanical fan problem (motor, bearings, seizing) or an electrical fault, and address it safely. So don't keep resetting it - get it properly investigated. So it's likely fan wear, seizing, or a fault - have it inspected and repaired. So then get it checked by an electrician or engineer. This is general guidance, not electrical advice.
No - a fan tripping is the fan's own protection responding to the fan over-drawing (usually grease strain), while the whole kitchen tripping under load is usually a circuit overload or fault across the electrics; they're related but distinct. No - a fan tripping out under load and the whole kitchen tripping the electrics under load are related but distinct. A fan tripping out is the fan's own protection (overload/thermal protection or its breaker) responding to the fan drawing too much current - usually because it's grease-strained and overheating (a fan-specific problem addressed by cleaning and checking the fan). The whole kitchen tripping under load is usually a broader electrical issue - circuits overloaded (too much equipment drawing current at once) or an electrical fault across the installation - which is mainly an electrician's matter (the extract fan being just one of many loads, and a grease-laden fan a possible minor contributor). So the two are different: one is the fan's own trip (fan strain, usually grease), the other is the kitchen's electrical circuits tripping (overload or fault). If just the fan trips, clean and check the fan; if the whole kitchen trips, get an electrician (as covered in the why-does-my-kitchen-trip-the-electrics-under-load page). So no - the fan's trip is fan-specific; the kitchen tripping is a broader electrical issue. So related but distinct. This is general guidance, not electrical advice.
A fan tripping under load usually means a grease-laden fan straining and over-drawing; we clean the whole system to TR19 Grease - removing the grease loading and straining the fan - and check its condition, so it runs on normal current, and flag any wear for repair. Ask us to clean and check your tripping fan. This is general guidance, not electrical advice.
