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Kitchen extraction cleaning - fan monitoring
The extract fan usually fails quietly, out of sight - straining under grease until, one day, it seizes or burns out mid-service. Sensors can change that: by watching for the signs of a struggling fan - rising vibration, dropping airflow, a straining motor - they can flag a failing fan early, before it fails. Here is how sensors detect a failing extractor fan, and why it is still the clean that fixes it. This is general commentary on fan monitoring.
The short answer
The extract fan is the component that most quietly fails - straining under grease, out of sight on the roof, until it seizes or burns out (as covered in the extractor-fan page). Sensors offer a way to catch that decline early. Here is how they detect a failing fan, and where the limits are. Why the fan fails unseen. The extract fan drives the whole extraction, but it is usually out of sight (on the roof or at the duct end), so its gradual straining under grease build-up goes unnoticed - until it fails (seizes or burns out), typically mid-service, causing a breakdown and emergency callout. The problem is that the decline is invisible. Sensors address exactly this by making the fan's condition visible as data. What sensors monitor. Sensors can detect a failing fan by monitoring the physical signs of a fan under strain: (1) Vibration - a grease-laden, unbalanced fan vibrates more than a clean, balanced one, and rising vibration is a classic early sign of a fan in trouble (imbalance, wear, a developing fault). A vibration sensor picks this up. (2) Airflow - as the fan and system struggle (grease-choked, fan straining), the airflow drops; an airflow (or pressure) sensor detects the extraction pulling less air. (3) Motor condition - a straining fan motor draws more current and runs hotter as it works harder against the grease load; current or temperature sensors detect this. (4) Noise - a straining fan runs louder; sound can be an indicator too. So the sensors watch the fan's vibration, airflow, motor current/temperature and noise - the physical signatures of a fan under strain. How the detection works. By monitoring these continuously and watching the trends, a sensor system can detect a fan that is failing: when the vibration is rising, the airflow dropping, the motor current or temperature climbing - especially trending steadily the wrong way - it signals that the fan is struggling and heading toward failure. The system can then flag an alert (a warning that the fan needs attention), often well before the fan actually fails. So the quiet, unseen decline becomes an early, visible warning. The value, and the limit. The value is turning a would-be surprise failure into an early warning - so the problem is caught and addressed as planned work (usually cleaning the system to remove the grease and free the fan, restoring it; sometimes a repair if there is a mechanical fault) rather than as a mid-service breakdown and emergency callout. But the sensor only warns - it does not fix anything. It is the clean (or repair) prompted by the warning that actually addresses the failing fan. And the sensor supports, not replaces, physical inspection (confirming the cause) and the underlying discipline of keeping the grease under control (the root cause of most fan strain). So sensors detect a failing extractor fan by monitoring its vibration, airflow and motor for the signs of strain, giving an early warning that a clean or repair is due - turning a quiet failure into a caught one. So sensors warn early; the clean fixes it. This is general commentary on fan monitoring.
Key points
The fan fails unseen
The reason sensors are useful for the extract fan is that the fan usually fails unseen - and sensors can make its hidden decline visible. The extract fan drives the whole extraction, but it is typically out of sight (mounted on the roof or at the far end of the ductwork). So as it strains under grease build-up - becoming unbalanced, loaded and worn - that decline happens where no one sees it. The result is that the fan often seems to fail suddenly (seizing or burning out, usually mid-service), when in fact it was declining quietly for a long time.
This invisibility is the problem sensors solve. By monitoring the fan's condition continuously and reporting it as data, sensors make the hidden decline visible - so the straining that would otherwise go unnoticed can be seen and acted on. Instead of the fan being a black box until it fails, its condition becomes trackable. So the sensors reveal the quiet decline that leads to the surprise failure - which is the basis for catching it early. The following sections cover what the sensors monitor and how the detection works. So the fan fails unseen - a quiet decline the sensors can reveal. So sensors can reveal the fan's quiet decline. This is general commentary.
What the sensors monitor
Sensors detect a failing fan by monitoring the physical signs of a fan under strain - chiefly its vibration, the system's airflow, and the motor's condition. Vibration: a clean, balanced fan runs smoothly, but a grease-laden, unbalanced fan (or one with developing wear) vibrates more - and rising vibration is a classic early indicator of a fan in trouble. A vibration sensor on the fan picks this up. Airflow: as the fan and system struggle (grease-choked, the fan straining), the extraction pulls less air - so a drop in airflow is a sign. An airflow or pressure sensor detects the extraction moving less air than it should.
Motor condition: a straining fan motor has to work harder (against the grease load and imbalance), so it draws more electrical current and runs hotter - so a rising motor current or temperature signals a struggling fan. Current or temperature sensors detect this. Noise: a straining fan also runs louder, so sound can be a further indicator. So the sensors watch these signatures - vibration, airflow, motor current and temperature, and noise - each of which changes as a fan strains toward failure. Together they give a picture of the fan's condition. No single reading is definitive, but the combination, tracked over time, reveals a fan in decline. So what the sensors monitor: vibration, airflow and the motor - the signs of strain. So they monitor vibration, airflow and the motor. This is general commentary.
How the detection works
The detection works by monitoring these signs continuously and watching the trends - a fan that is failing shows its signs steadily worsening over time. A single reading of vibration or airflow is a snapshot; the power of sensor monitoring is in tracking the readings continuously and seeing how they change. A healthy fan's readings stay fairly stable; a failing fan's readings trend the wrong way - the vibration steadily rising, the airflow steadily dropping, the motor current or temperature steadily climbing.
So the sensor system detects a failing fan by recognising these adverse trends: when the monitored values are moving steadily toward the danger zone (more vibration, less airflow, a hotter or harder-working motor), it signals that the fan is struggling and heading toward failure. It can then flag an alert - a warning that the fan needs attention - often well before the fan actually fails (while it is still declining, not yet broken). This is the key: the detection is early, based on the developing trend, not on the failure itself. So a fan that would have failed by surprise instead gives an early, data-based warning. So how the detection works: trends trending the wrong way trigger an early warning. So adverse trends trigger the early warning. This is general commentary.
An early warning, not a fix
It is important to be clear about what the sensor does and does not do: it gives an early warning that the fan is failing - but it is the clean (or repair) prompted by that warning that actually fixes the fan. The sensor detects and alerts; it does not remove grease or free a seized fan. So the value of the detection is realised only if it is acted on - by having the system cleaned (to remove the grease that is straining the fan, freeing and rebalancing it) or, if there is a genuine mechanical fault, repaired.
In most cases, the underlying cause of a failing fan is grease build-up (straining and unbalancing it), so the fix prompted by the warning is usually a clean - removing the grease to restore the fan. This is the crucial point: the sensor turns an unseen decline into an early warning, but the warning must trigger the clean (or repair) that resolves it. A warning ignored is no better than no warning. So sensors and cleaning work together: the sensor detects the failing fan early, and the clean (prompted early, as planned work) fixes it - before the fan fails and forces an emergency. So an early warning, not a fix - the sensor warns; the clean fixes. So the sensor warns and the clean fixes. This is general commentary.
Sensors plus sound cleaning
So sensors detect a failing extractor fan by monitoring its vibration, airflow and motor for the signs of strain, giving an early warning that a clean or repair is due - a valuable way to catch a fan's quiet decline before it becomes a mid-service breakdown. But the sensor is a warning aid, best used alongside the sound fundamentals: physical inspection (to confirm the cause when a warning comes) and, above all, controlling the grease that causes most fan strain in the first place. So sensors plus sound cleaning: catch it early, and control the grease.
The best approach combines both. Keep the extraction cleaned regularly (to the TR19 Grease standard, at a frequency matched to the cooking) - which removes the grease that strains the fan, preventing most fan trouble at source. And, where used, let sensors provide an extra early warning (catching any developing strain between cleans, or a mechanical fault). Together, the regular cleaning prevents the strain, and the sensors catch anything developing - so the fan is far less likely to reach a surprise failure. Sensors are a useful addition, not a substitute for the cleaning: the cleaning controls the root cause, the sensors add early warning. So use sensors (if you have them) to catch a failing fan early, and keep the extraction clean to control the grease that causes the strain - catch it early, and control the grease. So catch it early, and control the grease. This is general commentary on fan monitoring.
Questions
By monitoring the physical signs of a fan under strain - rising vibration, dropping airflow, and a straining motor (higher current or temperature) - and flagging when these trend the wrong way. The extract fan usually fails quietly, out of sight, so its decline goes unnoticed until it seizes or burns out. Sensors make the decline visible by monitoring the fan's condition: a vibration sensor detects the increased vibration of a grease-laden, unbalanced fan; an airflow or pressure sensor detects the extraction pulling less air as the system struggles; and current or temperature sensors detect the motor drawing more current and running hotter as it works harder. By tracking these continuously and watching the trends (vibration rising, airflow dropping, motor current or temperature climbing), the system detects a fan heading toward failure and flags an early warning - before it actually fails. So sensors detect a failing fan by monitoring its vibration, airflow and motor for the signs of strain. So they monitor the fan's strain signatures. This is general commentary on fan monitoring.
Increased vibration, dropping airflow, a motor drawing more current or running hotter, and rising noise - all signs of a fan straining, usually under grease build-up. A failing fan shows physical signs as it strains: it vibrates more (a grease-laden, unbalanced fan is not smooth); the airflow drops (the extraction pulls less air as the fan and system struggle); the motor works harder (drawing more electrical current and running hotter); and it runs louder (a straining fan is noisier). These are the signatures sensors monitor, and some are noticeable without sensors too (increased noise, weaker extraction - the noisier-but-weaker warning). The usual underlying cause is grease build-up, which unbalances and strains the fan. So the signs of a failing fan are rising vibration, weakening airflow, a straining/hotter motor and more noise - which, caught early (by sensors or observation), allow the fan to be cleaned or repaired before it fails. So the signs are vibration, weak airflow, a straining motor and noise. This is general commentary.
No - the sensor only warns; it is the clean (to remove the grease straining the fan) or a repair, prompted by the warning, that actually fixes it. A sensor detects a failing fan and raises an alert, but it does not remove grease or free a struggling fan - it only provides the warning. So the value of the detection depends on acting on it: having the system cleaned (which, since grease build-up is the usual cause of fan strain, removes the grease and frees and rebalances the fan, restoring it) or, if there is a genuine mechanical fault, repaired. So the sensor and the clean work together: the sensor catches the failing fan early, and the clean (or repair) fixes it - as planned work, before the fan fails and forces an emergency. A warning that isn't acted on achieves nothing. So no - the sensor warns, and the clean or repair fixes the fan. So no - the clean fixes it, prompted by the warning. This is general commentary.
No - some signs (rising noise, weakening extraction) are noticeable without sensors, and regular cleaning prevents most fan strain at source; sensors add an extra early warning but aren't essential. Sensors give a precise, continuous early warning, which is valuable - but they aren't the only way to catch a failing fan. Some signs are noticeable in the kitchen without sensors: the extraction getting noisier and weaker (the noisier-but-weaker warning) can signal a straining fan. And, more fundamentally, keeping the extraction cleaned regularly prevents most fan strain in the first place (by removing the grease that causes it) - so regular cleaning is the main protection, sensors or not. So you don't need sensors to look after your fan: regular cleaning (controlling the grease) does the most, and observation catches some signs. Sensors add a useful extra layer of early warning if you have them. So no - regular cleaning is the main protection; sensors are a helpful addition. This is general commentary.
Grease build-up - it unbalances and loads the fan, straining it until it seizes (grease jamming it) or burns out (the overworked motor); so the fix is usually cleaning. The extract fan accumulates grease like the rest of the system (on the impeller and housing), and this grease unbalances and loads it - so it works harder, vibrates and strains. Over time, the strain wears the fan, and it can fail: seizing (the grease, which can harden, jamming it) or burning out (the motor overworked and overheated). So grease build-up is the usual root cause of fan failure. This is why the fix for a failing fan (and the prevention) is usually cleaning - removing the grease to free and rebalance the fan and relieve the strain. It is also why sensor warnings usually lead to a clean, and why regular cleaning prevents most fan trouble. So grease build-up usually causes fan failure, and cleaning addresses it. So grease is the usual cause; cleaning is the fix. This is general commentary.
It can be a useful early-warning layer - catching a failing fan before a mid-service breakdown - but it works best alongside, not instead of, regular cleaning that controls the grease causing most fan strain. Sensor monitoring of the fan can be worthwhile: it turns the fan's usually-unseen decline into an early warning, so a failing fan can be caught and addressed as planned work rather than an emergency mid-service breakdown (which is costly and disruptive). That early warning has real value, especially for a critical, out-of-sight component. But it is an addition to, not a replacement for, the fundamentals: regular cleaning is what controls the grease that causes most fan strain (the root cause), and physical inspection confirms conditions. So sensor monitoring is worth it as an extra layer for those who want it - best combined with regular cleaning (which prevents most fan trouble) so the sensors catch anything that develops in between. So it can be worthwhile as an early-warning layer alongside regular cleaning. So yes, as an addition to regular cleaning. This is general commentary.
Sensors can warn of a failing fan, but grease is what strains it - and cleaning is what fixes it. We clean the whole system to remove the grease, free and rebalance the fan, and keep it running - addressing the cause a sensor only warns of. Ask us to clean your extraction and look after your fan. This is general commentary on fan monitoring.
