Kent · Air handling unit cleaning
Longfield AHU cleaning
AHU cleaning for Longfield, from a team that has been trading since 2009. Out-of-hours visits and 24/7 emergency callout.
- Stale or musty smells from the ventilation
- Dirty fans and fan housings
- Units that have only ever had filter changes
About our AHU cleaning in Longfield
All the building’s air passes through the fan, so dirt on the impeller and housing gets spread around. Fan, housing and the surrounding panels are cleaned as part of the job, once the unit has been shut down and isolated. If you are dealing with dirty fans and fan housings and units that have only ever had filter changes, we can put it right.
In rural areas, ventilation units are often in roof voids or outbuildings, which makes them easy to overlook.
Good records are part of the job. Each visit is written up with photos, covering the work done, any areas we couldn’t access and a recommended next date. Keep it with your fire safety records so it’s ready for an insurer, fire officer or EHO.
- Where
- Longfield (DA3)
- Wider area
- Kent
- Records
- Written report with pictures
- Price
- A fixed price before we start
- When we work
- When your site is closed, plus a 24/7 line
- Phone
- 0345 646 2711
- Last updated
- 30 October 2026
What AHU cleaning can’t fix
We’d rather tell you now than book work that will not help, so here are the limits:
- Damaged coils beyond cleaning
- Building management system faults
- Ventilation that was badly designed in the first place
Not sure which it is? You can give us a ring on 0345 646 2711 or use the quote form and we’ll tell you honestly.
What we work on in Longfield
- Dampers and louvres
- Internal panels
- Heating and cooling coils
- Filter sections
- Drain trays
- Supply and extract fans
Longfield: your questions answered
Do you work overnight in Longfield?
Yes, nights and weekends are routine for us. It means the site in Longfield keeps running as normal. Just call 0345 646 2711 or drop us a line with your opening times and we will plan around them.
Do you cover smaller places like Longfield?
Yes, Longfield is part of our area, however small the site. Just mention lanes, gates or anything else about the site when you book.
What is TR19?
TR19® is the BESA specification for keeping ventilation systems clean. TR19® Grease, a standalone specification since 2019, covers grease in kitchen extract systems, while TR19® Air covers other supply and extract ductwork.
Will we get paperwork for the AHU clean?
Yes, both a certificate and a report with photos. It includes a recommended date for the next check.
Can you price the work without visiting?
Typically, yes. Send a few wide photos plus close-ups of panels, filters or grilles, and we normally come back within one working day. If pictures aren’t enough, we will survey first.
Which sectors do you work in?
Restaurants and pubs, hotels, schools and colleges, hospitals and care homes, offices and retail, plus food production and leisure sites.
Can you set up regular visits?
Yes. Plans on a 3, 6 or 12-monthly cycle are available, to suit the system and how it’s used.
Do you survey before quoting?
Yes. Photos often do the job, while bigger or harder-to-see systems are surveyed on site.
Also near Longfield
Other services in Longfield
Why deal with it now?
If people in a building in Longfield complain about stuffy or smelly air, the AHU is worth looking at. Cleaning it deals with the cause rather than the symptom. It’s simpler to plan the work at Longfield now than to arrange it in a hurry later.
Whatever the type of site, the quote works the same way: how much there is, how we reach it, what state it’s in and when we can work. Call for a fixed quote and we will explain each part.
Why choose Duct Doctor in Longfield
- A fixed price before any work starts
- One number for every site across the South East and London
- CHAS and SafeContractor accredited, with ISO 9001
- Every job surveyed first
Read our cost guide or how to check a contractor.
Fixed quotes for AHU cleaning in Longfield
The diagnosis comes before the price. We look at:
- How big the system is
- Site requirements such as sign-in and permits
- Parking and loading at the site
- What state the system is in
Combining work into one visit or one programme can make for a more efficient booking. Mention every system or site you need covered, and you will get one fixed quote.
Helping us quote
To help us quote quickly, please include:
- Where the plant sits or the system leaves the building, such as a roof or outside wall
- The paperwork from the last visit, if you have it
- Where the site is and what kind of site it is
- Wide pictures of the system and the area around it
The quickest way to a quote is to send photos: wide shots of the system, close-ups of anything that worries you and how we’d get to it. Tell us what kind of site it is and when it’s open, and many jobs can be priced from that alone.
Multi-site and managed buildings
From a single site to a large estate, you get the same standard: diagnosis, a fixed price, work booked around your hours and a written report with pictures.
If you look after several sites, we can schedule visits across all of them on one quote. Each site gets its own report and photos, so each one has its own record.
AHU cleaning in Longfield: local notes
There are about 11 schools, colleges and universities and about 11 care, childcare and hospital premises on the FSA’s food hygiene register across Longfield and its immediate surroundings (about a mile and a half). Many buildings of this kind have supply and extract ductwork that gathers dust and needs inspecting. Longfield, about 19 miles from central London, is within our usual area. Visits are booked around your hours, evenings and weekends included. Longfield’s nearest hospital, Darent Valley Hospital, is about 3.3 miles north-west. Clean air matters most where people are unwell, and that is as true in a care home as in a hospital.
Healthcare ventilation, from large hospitals like Darent Valley Hospital (about 3.3 miles north-west) to small clinics, depends on clean filters, coils and ducts. For workplaces around Longfield station with mechanical ventilation, cleaning can be done in the evening or at weekends. For schools like Longfield Academy, the holidays are the usual time to inspect and clean ventilation.
Longfield is about 3 miles south-west of Northfleet, in Kent. Wherever you are in the DA3 postcode area, we cover AHU cleaning for commercial sites. Our area takes in 922 places across Kent, large and small. For sites nearby, see our Maidstone page (13 miles or so).
Here we cover the DA3 postcode area for AHU cleaning. We cover sites on Station Road, Main Road and Ightham Close and nearby roads. Neighbouring places we cover for AHU cleaning include Hartley (1 mile south), New Barn (1 mile east), Longfield Hill (1 mile south-east), New Ash Green (2 miles south) and Nash Street (2 miles east). Within a short drive, we also cover Maidstone (13 miles south-east), Dartford (5 miles north-west), Sevenoaks (10 miles south-west), Gravesend (4 miles north-east), Tonbridge (14 miles south) and Northfleet (3 miles north-east).
Landmarks near Longfield
Typical jobs here are in premises near Railway Tavern, Hartley Primary Academy and Rectory Meadow, among other places. There’s a railway station in Longfield itself: Longfield station. Nearby you will also find Darent Valley Hospital (3.3 miles north-west) and Stone Castle (3.4 miles north). Not far away are Sawyers Lake.
What happens on the day
Everything the job needs comes with us, including protection sheets, the right tools and access kit. You only need to give us clear access and switch off what needs to be off. The visit takes a single shift for a typical unit, longer for large or heavily soiled ones. If the van will struggle with a lane or gateway near Longfield, let us know and we’ll plan around it.
- We start with a survey of the unit and a fixed quote for the work.
- We arrange the shutdown with your staff and sheet the area.
- Filters are dealt with as agreed, and the coils, fan and casing cleaned.
- Standing water and slime come out of the tray and the drain is checked.
- A TR19® certificate and photo report follow the clean.
Before we arrive
- Plan for cooking equipment or plant to be off before we arrive
- Name a contact who can let us in at the agreed time
- Have your last certificate or report to hand
Getting a quote
Quoting starts with a diagnosis, from your pictures and details or, where that is not enough, a survey on site. Then we send a fixed price, before work begins.
Advice
Staff cleaning versus specialist work
For ventilation and air handling systems, in-house care is mostly about checks: keeping grilles clear, noting unusual noise or smells and logging filter changes. The inside of ducts and units needs a specialist.
A few tasks are always specialist work: entering ducts, working on fans, testing dampers and taking grease readings call for the right kit, training and safe access. Leave those to us.
Part by part
Heating and cooling coils
Cooling coils stay damp in use, so dirt on them can turn sticky. The coil and its drain tray are cleaned as one job.
Drain trays
Condensate from the coil drips into a tray beneath it. We clear standing water, clean out slime and check the outlet is draining.