Cooker Hood Not Working in Petersfield - Common Faults and What Really Causes Them

Published August 2026 | Cooker Hood Not Working Common Faults

Most people assume that when a cooker hood stops working, the motor has burned out and the whole unit needs replacing. That assumption sends homeowners across Petersfield and the wider Hampshire area down an expensive and completely unnecessary path. In reality, the most common cooker hood faults are simpler, cheaper, and far more avoidable than the myths suggest.

Myth: A Dead Cooker Hood Always Means a Dead Motor

The reality

Our engineers hear this one constantly. A homeowner calls in convinced their Bosch or Hotpoint extractor hood has completely packed up, only for a quick diagnosis to reveal a tripped circuit breaker. Or a blown fuse. Or a thermal cutout that has triggered because the filters have not been cleaned in over a year.

Before assuming the motor is the culprit, work through the basics in order:

1. Check whether the hood is getting power at all - test the circuit breaker and any isolator switch above the unit.
2. If the hood uses a plug connection, check the fuse - commonly a 3 amp or 5 amp fuse on older installations.
3. Check whether the thermal cutout has tripped. This is a safety device that shuts the motor down when it overheats, which happens when airflow is restricted by blocked or saturated filters.
4. Test the controls carefully. A completely unresponsive control panel more often points to a failed capacitor or a control board fault than a dead motor.

When our engineers run a fault through the Voltrade GoFIX diagnostic tool on a "dead" cooker hood, a full motor failure is actually one of the less common findings. In most cases the fault is electrical rather than mechanical. Motor replacement does happen - and on a budget Beko or basic entry-level model, it can sometimes make more sense to replace the unit outright - but it is not the conclusion a thorough engineer reaches without working through everything else first.

Myth: A Noisy Cooker Hood is About to Break Down

The reality

Rattling, humming, vibrating, grinding - a noisy cooker hood sounds alarming, and many homeowners ring us expecting to hear that the motor is on its last legs. More often than not, the noise has nothing to do with the motor at all.

Grease filters that are not seated correctly vibrate noticeably at higher fan speeds. Charcoal carbon filters in recirculating hoods rattle when they become saturated and start to break down internally. Loose fixings on the canopy or duct connections create a low-frequency drone that sounds like it is coming from deep inside the unit. Even a build-up of grease on the fan blades causes an imbalance that produces a rhythmic wobble and noise at higher speeds.

Diagnosis matters here. A grinding noise that gets progressively worse over weeks does point to motor bearing wear, particularly on older units. But a rattle, an intermittent buzz, or a vibration that appears at specific fan speeds is almost always something more manageable. Clean the filters, check they are properly seated, and inspect the duct connections before anyone calls it a motor problem.

Myth: You Only Need to Clean Cooker Hood Filters Once a Year

The reality

This is the myth that causes the most actual damage. Grease filters - the metal mesh panels fitted to virtually every ducted extractor hood - need cleaning far more frequently than most people realise. In a household where cooking happens daily, cleaning every four to six weeks is a sensible target. For heavier cooking households, every three to four weeks is better.

When grease filters become saturated, several things happen at once. Airflow drops sharply, so the hood stops extracting effectively even though the motor is working fine. The motor then has to work harder to pull air through a restricted filter, which raises operating temperature and accelerates wear on the bearings and windings. In the worst cases, the thermal cutout trips and the hood appears completely dead.

Most metal grease filters are dishwasher-safe. Pop them in on a hot cycle and they come out clean. It takes five minutes and costs nothing. This single maintenance habit prevents more cooker hood breakdowns than any other action a homeowner can take.

Carbon filters on recirculating hoods - the type commonly fitted in Petersfield kitchens where routing ducting to an outside wall is not practical - cannot be cleaned. They need replacing. Typically every three to six months depending on how heavily the kitchen is used. A replacement carbon filter set for a common Hotpoint or LG model typically costs between 15 and 35 pounds. Ignoring them does not just reduce performance; it puts unnecessary strain on the motor as it fights against solid, saturated filter media.

Myth: If the Hood Runs but Doesn't Extract, the Motor Needs Replacing

The reality

A cooker hood that runs but fails to remove smoke, steam, or cooking smells is one of the most common complaints our engineers deal with in Petersfield. The assumption is nearly always that the motor is weak. That is rarely the case.

Poor extraction is almost always a system problem rather than a motor problem. The most common causes our engineers find are:

1. Blocked or saturated grease filters - as above, these choke airflow even when the motor is running at full speed.
2. Blocked or kinked ducting - particularly common in older Hampshire properties where the original installation took shortcuts on duct routing. One extra 90-degree bend, or a section of collapsed flexible duct, can substantially reduce extraction performance.
3. A stuck external vent flap - the flap on the outside wall that should open when the hood runs. These seize with grease and weathering over time. A flap that only opens partway dramatically limits airflow.
4. A recirculating hood running without the correct carbon filters installed - or a convertible hood set to the wrong configuration entirely. This sounds unlikely but our engineers encounter it regularly.
5. A hood undersized for the cooking equipment beneath it - an extraction rate of around 400 cubic metres per hour handles a standard four-burner gas hob adequately, but a range cooker or high-output wok burner needs considerably more capacity.

On Bosch and Neff hoods specifically, our engineers commonly find that the electronic speed controller has developed a fault preventing the hood from reaching higher fan speeds. This gives the impression of a weak motor when the motor itself tests perfectly fine.

Myth: Cooker Hood Repairs are Always Expensive - Better to Just Replace

The reality

This myth is partly true in very specific circumstances and wrong in most others. For a budget recirculating hood that cost 80 pounds new, spending 60 to 90 pounds on parts alone for a motor replacement does not make financial sense. But that is a narrow scenario, not a general rule to live by.

Many of the faults our engineers find in Petersfield homes cost very little to rectify. A tripped thermal cutout is free to reset once the underlying cause is addressed. A failed run capacitor - one of the more common electrical faults on single-phase extractor motors - typically costs between 20 and 50 pounds including labour to replace. A blocked external vent flap that needs freeing and cleaning is a job that takes under an hour. Replacing a set of carbon filters for a Samsung or LG recirculating hood is a 20 to 30 pound fix.

Even motor replacements are not always prohibitive. On a mid-range or premium hood from Bosch or Siemens, a motor replacement typically costs between 80 and 160 pounds in parts. Add an hour of skilled labour and the total comes to around 150 to 280 pounds - often less than the cost of a new equivalent hood supplied and installed. If the unit is less than eight years old and otherwise in good condition, repair is commonly the better financial decision.

The key is getting a proper diagnosis before authorising any parts. The Voltrade GoFIX tool is built for exactly this - cutting through guesswork so a homeowner knows precisely what they are paying for before any work starts. A quote for a motor before an engineer has even checked the filters is a reason to ask more questions.

Myth: All Cooker Hoods Work the Same Way

The reality

Understanding what type of hood you have changes everything about how to diagnose a fault. There are three main configurations, and they fail in different ways for different reasons.

Ducted hoods extract air directly outside through ductwork. When these fail to extract properly, the fault is almost always somewhere in the duct route, at the external flap, or in the filters. The motor is rarely the first suspect.

Recirculating hoods pull air through grease and carbon filters and push it back into the kitchen purified. There is no ductwork and no external flap. When these stop working effectively, it is nearly always the carbon filters that need replacing. Motor failure does occur but is less common than simple filter neglect.

Convertible hoods can operate in either mode and are increasingly common in Hampshire new-build homes and renovated kitchens. These are sometimes found running in the wrong configuration - with duct-mode settings active but no duct connected, or recirculating mode active without carbon filters installed. The hood appears broken when it is actually misconfigured.

What Actually Matters - Expert Advice

After diagnosing cooker hoods across Petersfield and across Hampshire, the patterns are clear. Most cooker hood faults come from one of three root causes: insufficient filter maintenance, a problem with the original installation, or an electrical fault that has nothing to do with the motor. Mechanical motor failure is a real fault mode, but it is significantly less common than the myths would have you believe.

Here is what makes a practical difference:

1. Clean grease filters regularly. Every four to six weeks if you cook daily. It takes a few minutes and prevents the majority of performance problems before they develop.
2. Replace carbon filters on schedule. Every three to six months on recirculating hoods. Carbon filters cannot be washed - once they are saturated, they need replacing.
3. Check your ducting if performance is poor. Every additional bend in a duct run reduces extraction efficiency. A qualified engineer should inspect the duct route if the hood is underperforming despite clean filters.
4. Act on early warning signs. Reduced extraction, unusual noises, and intermittent behaviour are early-stage faults. Catching them before they develop into complete failures is almost always cheaper.
5. Get a diagnosis before agreeing to parts. A competent engineer will tell you what is wrong before quoting for any repair work.

For homeowners in Petersfield, repair costs rise alongside everything else. Consistent maintenance keeps those costs down and keeps the hood working as it should for longer.

Myth-Busting Questions

Can a faulty cooker hood create a fire risk?

It can in specific circumstances. A heavily grease-saturated filter sitting above a gas hob is a real hazard if grease ignites. Thick grease build-up on internal fan blades and motor housings can also smoulder at high temperatures. This is not a common event, but it is one practical reason why filter cleaning is a safety matter as well as a performance one. Our engineers recommend never leaving filters more than eight weeks between cleans in a kitchen used daily.

My cooker hood light works but the fan won't run - what does that tell me?

It tells you the hood is receiving power, which rules out a total electrical supply failure straight away. Lighting and fan circuits are separate on most hoods - Hotpoint, Beko, and Bosch models included. This narrows the fault to the fan motor itself, the run capacitor, the speed selector switch, or the main control board. None of those are automatically write-off faults, and a proper diagnosis will quickly identify which one is at fault.

Is it worth repairing a cooker hood that's over ten years old?

Age alone does not determine whether repair makes sense. The relevant questions are whether parts are still available, whether the fault is electrical or mechanical, and whether the repair cost is proportionate to the unit's value. A ten-year-old premium Bosch or Neff hood with a capacitor fault is worth repairing. A ten-year-old budget recirculating model needing a new motor typically is not. An honest engineer will tell you which situation you are in before any money is spent.

How much does cooker hood repair typically cost in Petersfield?

Repair costs vary considerably depending on the fault and the appliance. Simple fixes - filter replacement, resetting a thermal cutout, clearing a stuck vent flap - cost very little beyond the call-out charge. Capacitor replacements typically come to between 40 and 80 pounds including labour. A full motor replacement on a mid-range hood typically costs between 150 and 280 pounds all in. Getting a diagnosis first means you know what you are dealing with before committing to any work.

How do I know if my cooker hood is ducted or recirculating?

Look for a pipe - either round or rectangular - leading from the top or rear of the hood into a wall or ceiling void. If there is a visible duct, the hood extracts outside. If there is no duct and the hood has charcoal carbon filters sitting behind or above the metal grease filters, it is a recirculating model. In many Petersfield and Hampshire homes built or renovated in the last two decades, recirculating hoods are common where kitchen layout made external ducting impractical.

Why does my cooker hood smell bad even when it's running?

On a recirculating hood, a persistent smell almost always means the carbon filters are exhausted and need replacing - they are no longer absorbing cooking odours effectively. On a ducted hood, bad smells coming back through the unit often point to a broken or missing external vent flap allowing outside air - and whatever is near the vent outside - to flow back through the duct. Built-up grease inside the duct itself can also produce unpleasant smells when the hood runs and disturbs it.