Call Us
Book a Repair
We all know about the magic that cooker hoods create in our kitchens. They eliminate odours, extract smoke and steam, remove oil and grease splashes and more. No matter what brand of cooker hood you have in your home, one thing’s for certain.
With wear and tear, you’re bound to see error symbols pop up from time to time. If you want to know what they mean and what subsequent steps you need to take, this post is for you.
Keep reading to get a better understanding of your appliance and to know when it’s time to call in a pro if a fault arises. Let’s begin.
Your Cooker Hood Symbols Quick Reference Guide (With Extractor Hood Symbols Table)
A cooker hood is a complex appliance performing heavy-duty work. At times, it can show error codes or display flashing lights that indicate some type of problem. You need a quick reference guide to help you decipher the meaning quickly and conveniently. And that’s exactly what we provide you with below.
Our easy table takes you through some of the most common problems and what to do about it. From a fan speed icon and lamp icon to your grease filter indicator and charcoal/odour filter indicator, timer and lock/child lock, we’ve got you covered.
Take a look at what your Hob2Hood communication means and what steps you can take to resolve minor issues yourself before calling in expert help for your extractor hood repairs.
| Icon / Symbol | What it Means | Quick Action | Where You’ll See It |
| Fan / propeller / bars 1–3 | Extraction speed level | Use the lowest speed that clears steam; choose high for frying, then step down to cut noise. | All brands. “P” or “Boost” may indicate a temporary max mode. |
| Light bulb | Hood light on/off | If the light fails: check bulb/module type (GU10, G4, LED module) and driver; isolate power first. | Older models = halogen, newer = LED + driver. |
| F (sometimes “A”) / filter icon | Filter service reminder | Clean the grease filter; replace charcoal/odour filter if fitted; then reset the indicator. | Widespread. On Bosch/NEFF/Siemens, see “1” and “2” rows. |
| “1” flashing (LED 1) | Grease filter saturated | Remove metal filters; clean (often dishwasher-safe); dry fully; reset. | Common on Bosch/NEFF/Siemens; “1” = grease filter. |
| “2” flashing (LED 2) | Charcoal/odour filter due | Replace charcoal filter (non-washable on most models); reset. Long-life/regenerable types on some models. | Common on Bosch/NEFF/Siemens; “2” = odour filter. |
| Padlock / key | Child lock active | Unlock via the panel combo (varies by brand); if stuck, power-cycle and retry the combo. | Often a long-press on a settings key enables/disables. |
| Clock / hourglass | Timer / run-on | Use to clear odours after cooking (10–15 minutes); disable if noise is an issue at night. | All brands; some let you set a default run-on. |
| “P” / Boost / double-arrow | PowerBoost (temporary max) | Use for strong odours; avoid long sessions to reduce noise/back-drafting. | Bosch/NEFF/Siemens: “Intensive”/“Boost”. |
| Auto / nose icon / waves (sensor) | Automatic extraction (air-quality sensor) | Good for simmering; switch to manual for heavy frying if Auto lags. | “PerfectAir” on some Bosch/Siemens; names vary by brand. |
| Hob²Hood / hob + waves | Linked control from the hob | Works only if both hob and hood support it; pair/activate in each manual; manual override is fine. | AEG/Electrolux ecosystem + a few others. |
| Looped arrows / house icon | Recirculation mode (no outside vent) | Fit/maintain the charcoal filter; expect lower airflow than ducted setups. | Installers can switch between ducted/recirculating in settings. |
| Arrow through wall / external vent | Ducted mode (vent outside) | If weak, check duct diameter/bends and outside grille; see not extracting checks. | Best with a 150 mm round duct; avoid tight bends. |
| All LEDs flashing together | Service/clean reminder (often filters) | Clean/replace filters, then reset. If it persists, the sensor/PCB may need diagnosis. | Some premium brands (e.g., Novy) use this pattern. |
| Bell / beep icon | Acoustic signal enabled | Toggle in settings if you prefer silent keypresses. | Not on all models. |
Reset the Filter Light on Popular Brands (Matrix)
The filter light isn’t a fault. Rather, it’s a saturation indicator that counts run-time. When you see “F” flashing or a numbered LED (often 1 = grease; 2 = odour/charcoal), it’s time to clean or replace your filters and then perform a reset.
Start by identifying your filter type: metal grease (washable, usually dishwasher-safe) and charcoal/odour (replaceable unless your model supports regeneration).
After cleaning/replacement, reseat the filters fully and dry the metal meshes before refitting. Then, use the brand’s button combo to clear the reminder.
On many panels, this is a 3-second hold on the reset/settings area while the indicator is lit (some are 3–5 seconds; remember that labels vary by model). If the light persists, power cycle the hood at the isolator for around one minute and try again.
On recirculating installations, confirm the charcoal filter indicator is activated (some brands ship it off by default) and check you actually changed the charcoal filter (and did not just clean the grease mesh).
If it still flashes after a correct reset, the issue can be with the sensor/PCB, so it’s worth booking a professional diagnosis.
Use the matrix below for quick, brand-by-brand cues.
Still not getting it right and you need help? Why not call in a Domex pro who can help with all types of common cooker/extractor hood problems?
| Brand | Indicator Name | Button combo (hold time) | What to do when a reset fails |
| Bosch/NEFF/Siemens | LED 1 (grease) LED 2 (odour) | After cleaning or changing the filter, reset the saturation indicator, which is often a short hold on the panel. For older models, press and hold to reset while the indicator flashes. | Get in touch with a pro at Domex |
| AEG/Electrolux | F/C filter warnings | Clean/replace and reset the filter alarm after maintenance after a 2-3 second hold on the panel key. | Get in touch with a pro at Domex. |
| Beko | F/A flashes indicate grease/charcoal. | Reset by holding the specified key for around five seconds until the flashing stops. E.g. press A for five seconds or press function + speed 3 for three seconds to clear the filter warning. | Get in touch with a pro at Domex. |
| Hotpoint | Flashing LED lights are warnings | Perform T-key resets and charcoal LED activation by pressing T2+T3, depending on your model. | Get in touch with a pro at Domex. |
| Elica | F and/or C | Press and hold for approximately three seconds to reset. If both F and C appear, reset twice. Activate the charcoal indicator for recirculation. | Get in touch with a pro at Domex. |
Filter Light Flashing But Won’t Clear? (Decision Tree)
Is your filter light flashing and still won’t clear? It’s time to take the following steps:
Begin by confirming your filter type, whether it’s metal or charcoal. Then, switch off your appliance at the power source and remove the filter. After this, you’ll want to clean it properly.
Bear in mind that while some models are dishwasher safe, others may need to be replaced entirely (particularly true for charcoal models). Next, reset the filter and press the relevant reset combo. In most cases, you’ll want to hold the button combination for around three seconds.
Then, power your appliance back on and check the recirculation vs ducted settings. If the light is still flashing, you’ll want to book expert repairs because the likelihood of a PCB or sensor being faulty is very high.
Wondering do you need an extractor hood in your kitchen? Or do you need reliable extractor hood repairs? Count on Domex to help. Book a local engineer today.
Cooker Hood Not Extracting: Quick Checks That Actually Help
Clogged filters are one thing but when your extractor hood is not performing its main function – which is extracting – that’s a problem. There are many reasons this could happen. Here’s a quick checklist of possible problems that could be causing the issue:
- Grease filter is clogged
- Charcoal filter is spent
- Duct diameter is too small (125mm vs 150mm)
- Too many bends
- Kinked hose
- Outside grille is blocked
- Stuck non-return flap
- Impeller grease build-up
- Motor/capacitor fatigue
- Hood is too high above the hob
- Negative pressure in the room
Your first port of call is to check all your bends/elbows for kinks. Also check that your mounting height is correct. A distance beyond the recommended norm will not produce the desired results. Check the duct length, too, as this affects the airflow that removes odour and smoke from your kitchen and takes it outside.
Next, perform impeller cleaning while following all the safety precautions. And finally, it’s time for the paper test. Switch on your appliance and place a piece of paper under the suction vents. If the paper doesn’t remain there but floats down, you’ve got a problem.
Luckily, the team at Domex consists of more than 70 field engineers who are experts in appliance repairs, including cooker hoods.
We serve areas that include Leicester, Nottingham, Croydon, Coventry, West Berkshire, Reading, Crawley and more. This means local availability at affordable prices and quick response times, when you need it most.
Noisy Cooker Hood (Buzzing, Rattling, Whistling)
Another aspect that can raise concern when it comes to your cooker hood refers to the amount and type of noise it is emitting. While a regular sound is healthy, buzzing, rattling or whistling sounds indicate a problem. This problem can be caused by a range of factors, among which include:
- Loose baffles/filters
- Fan wheel imbalance
- Vibration mounts perished
- Duct resonance
- Water/condensation in duct
- High speed usage
- Cabinet coupling
Whichever the cause is in your case, you’ll want to start by checking your mounting screws and then observing the vibration isolation. Also check for any condensate that may have built up. If these quick DIY checks don’t work, you’ll need expert help that may recommend installing anti-vibration pads.
Grease vs Charcoal Filters: Cleaning, Replacement and Reset Reminders
You may not be aware but there are important differences between grease and charcoal filters, each of which requires a different approach to care and maintenance. Here are some differences and notes you should be aware of when managing your extractor hood cleaning schedule:
- Grease filter cleaning: Regularly clean the grease filters. Many are dishwasher-safe. This will help maintain airflow and prevent odour saturation and buildup. Make sure they are completely dry before reinstalling to avoid damage or reduced efficiency.
- Charcoal/odour filter replacement intervals: Replace your charcoal filters every few months, depending on usage, as they lose effectiveness over time. Don’t forget to use the reset sequence of the filter indicator after replacement to ensure accurate maintenance reminders.
- Long-life filter regeneration: Some cooker hoods use long-life filters that can be regenerated by heating in the oven, extending their lifespan and reducing waste. In these cases, you’re not likely to see the appearance of spare parts codes on your display. It’s important to always follow the manufacturer’s instructions for proper regeneration and performance.
Cooker Hood Lights Not Working (Halogen/LED/Driver)
The most common types of lights for cooker hoods are halogen, LED and driver lights. When these stop working, you’ll want to change them for optimal cooker hood performance.
This means first identifying the bulb type. Then, you’ll need to test the switch for the power source of the appliance to see if the fault is related to the light or to the power supply.
We strongly advise you to take the greatest safety precautions when you do this to avoid health and hazardous situations from arising. Next, you’ll want to swap the old bulb out with the new one. Be sure to pay close attention to whether it’s a screw or pin type (GU10, G4).
Then, once done, plug in your appliance again and check the LED module to see if the LED driver is displaying correctly. If you see flickering lights after performing the bulb change, this indicates a PCB fault.
For safety reasons, you’ll want to contact an experienced appliance engineer to isolate the power, check the LED driver and PCB, monitor for any potential socket corrosion and perform other necessary checks to get your appliance back in optimal working condition once again.
Need help with your cooker hood light repair? Book our extractor hood repair service today!
Find Your Model Number and Why It Matters
The right model number for your extractor hood appliance is the very first starting point for figuring out what needs to be done, from a light reset to filter cleaning.
This valuable information will also help you determine what spare parts may be needed in the event of a repair or maintenance service.
If you’re wondering about your model sticker location, first check behind the grease filter or the underside panel.
Once you locate it, you’ll see a serial number on a sticker that you can quote when getting in touch with us for the most accurate and pinpoint precise service.
FAQs: Cooker Hood Symbols, Reset Filter Light, Not Extracting and More
- What does the F symbol mean on my extractor?
The F symbol usually indicates that the grease or charcoal filter needs cleaning or replacing, depending on your cooker hood model.
- How do I reset the filter light on Bosch/NEFF/Siemens?
Press and hold the filter reset button (often marked “F” or the timer icon) for a few seconds until the light goes off. Check your manual for the exact button combination.
- How often should I replace a charcoal filter?
Charcoal filters typically need replacing every 3–6 months, depending on how often you use your cooker hood.
- Why is my hood still noisy after cleaning?
A hood may remain noisy if the fan motor is worn, the ducting is too narrow or there’s a blockage restricting airflow.
- Can I run a hood without a duct?
Yes, you can use a recirculating hood without external ducting, but it must have a charcoal filter to remove odours effectively.
- What is Hob2Hood and will it work with any hob?
Hob2Hood is a wireless technology that allows compatible hobs to control the hood’s fan and lights automatically. It only works with matching brands and compatible models.
- What duct size is best: 125mm vs 150mm?
A 150mm duct is generally better as it reduces noise and improves airflow efficiency compared to a smaller 125mm duct.
- Why does my hood drip condensation?
Condensation drips can occur if the ducting is too long, poorly insulated or if cold air meets warm, moist kitchen air inside the vent.
- Does child lock affect symbols?
Yes, when child lock is activated, it can disable buttons or make symbols flash, preventing any settings from being changed.
- When should I book a repair instead of DIY?
Book a professional repair if cleaning, filter changes or resets don’t solve the issue. This is especially true for electrical, motor or control panel faults.
Areas We Cover for Extractor Hood Repairs
At Domex, we’re all about providing you with a trusted and reliable local service. That’s why our engineers can respond quickly and efficiently to your requests for professional cooker hood repairs. We serve a wide variety of areas, including:
Contact us for reliable cooker hood repairs today!