Kent · Air handling unit cleaning
Thong AHU cleaning
AHU cleaning for Thong and the surrounding area: a survey, a fixed price, careful work and proper paperwork. Ask us for a fixed quote.
- Fan sections that haven’t been cleaned in years
- Coils clogged with dust and debris
- Leaves and litter drawn into the unit
AHU cleaning in Thong, done properly
An AHU clean is a thorough examination and treatment of the unit. We look inside each section, clean what we find and record it with pictures, so you can see the unit’s condition for yourself. If you have air handling units never cleaned inside and coils clogged with dust and debris, we can put it right.
For a building in or near Thong, access is agreed in advance and the visit is planned around the journey, and the ventilation is inspected, cleaned and recorded the same as anywhere.
Every visit ends with a written report and pictures, so you have a record of what was done and when. Where the work is a TR19® Grease clean, the certificate is issued through the BESCA Vent Hygiene Elite portal.
- Where
- Thong (DA12)
- Region
- Kent
- Records
- Photo report after each visit
- Price
- A fixed price before work begins
- When we work
- When your site is closed, plus a 24/7 line
- Telephone
- 0345 646 2711
- Reviewed
- 30 October 2026
Why it’s worth doing now in Thong
Standing water in a drain tray doesn’t clear itself. Left alone, it can overflow, leak into the plant area or ceiling below and spread smells through the system. Dealing with it early keeps the clean straightforward. If the system at a site near Thong fails, there may be nowhere nearby to move to.
When the work has to happen, how we reach it and how big the site is can all change the price. Each of those is built into the quote and give you a fixed price before work begins.
Why choose Duct Doctor in Thong
- We are fully insured
- BESCA Vent Hygiene Elite member, cleaning to BESA TR19® Grease
- Fixed quotes, typically within one working day
- Accredited under CHAS and SafeContractor, with ISO 9001
Take a look at what affects the cost or our accreditations.
Thong buildings and their air
There are about 18 schools, colleges and universities and about 4 hospitals, care homes and childcare premises on the FSA’s food hygiene register in and around Thong, up to about a mile and a half out. Buildings like these often rely on mechanical ventilation, which TR19® Air covers. About 22 miles out from central London, Thong is part of the South East area we work across. The visit is fixed around your opening hours, not ours. For Thong, the closest hospital is Gravesham Community Hospital, roughly 2.8 miles north-west. Healthcare buildings depend on clean supply and extract ventilation, and the same applies to surgeries, clinics and care homes.
Gravesham Community Hospital, about 2.8 miles north-west, is the nearest hospital to Thong, and healthcare sites of every size need their supply air kept clean.
Thong is about 2 miles south-east of Gravesend, in Kent. We provide AHU cleaning for businesses, landlords and public buildings in Thong and the rest of Kent. 922 places in Kent are on our list, large and small. For sites nearby, see our Maidstone page, about 11 miles away.
We cover every part of the DA12 postcode area for AHU cleaning and the roads nearby. Neighbouring places we cover for AHU cleaning include Upper Ifield (1 mile east), Shorne Ridgeway (1 mile east), Shorne (1 mile east), Chalk (1 mile north) and Higham (2 miles east). Further out, we also cover Maidstone (11 miles south-east), Sittingbourne (15 miles east), Dartford (8 miles west), Sevenoaks (13 miles south-west), Northfleet (3 miles north-west) and Swanley (10 miles west).
Near you in Thong
We work in commercial kitchens and buildings around Shorne Woods Country Park and Thamesview School and the streets around them. For rail, the closest station is Sole Street station, roughly 2.2 miles south-west. A little further out are Rochester Castle (4.5 miles east) and Gravesham Museum (2.6 miles north-west). Open spaces near Thong include Rede Common and Gad's Hill.
Looking after it afterwards
Simple habits between visits make a real difference. Our advice:
- Plan the next inspection before the last report gets filed away
- Report stiff or damaged access doors
- Store the TR19 paperwork where auditors can find it
- Keep the area around the fresh air intake clear
The ducts served by the unit may need attention too. Cleaning the unit and ducts together gives the best result, and we can survey both.
Regular filter changes are the best protection an AHU has. Once filters clog, dirt starts getting past them.
Staff cleaning versus specialist work
When your team notices a problem between visits, such as dripping grease, a noisy fan, a smell or a filter that will not come clean, it’s best reported rather than tackled in-house. We can diagnose it and quote.
Logging matters as much as cleaning. A dated log of in-house cleaning and checks helps show that the system is managed between specialist visits, alongside our reports.
Signs you need AHU cleaning in Thong
Filters that are not changed or cleaned on time clog up, which cuts the airflow and can let air slip round the filter. After that, the coils and fan collect what the filter should have caught.
Look out for any of the following:
- Dirty coils holding back the airflow
- Debris and leaves in the fresh air intake
- Air handling units due a clean after building work
- Dirty fans and fan housings
For schools like Riverview Infant School, the holidays are the usual time to inspect and clean ventilation.
Comparing quotes
- How VAT is shown on the quote
- If the quote is a fixed price or an estimate
- Whether the quote is based on a survey or photos
- What’s included in the scope, part by part
What AHU cleaning cannot fix
Not every problem is solved by AHU cleaning, and we’ll tell you before we start. It doesn’t solve:
- A system that is undersized for the building
- Leaking heating or cooling coils
- Mechanical faults with motors, belts or bearings
If in doubt, give us a ring on 0345 646 2711 or send us an email and we’ll say what we think before booking.
Where we work
- Filter sections
- Internal panels
- Drain trays
- Dampers and louvres
- Heating and cooling coils
- Supply and extract fans
Thong questions
Can you work in Thong outside opening hours?
Yes, we can come after you close and finish before you open. The work in Thong can fit around your hours. Tell us your opening hours when you ask for a quote.
Is Thong within the area you cover?
Yes, we work in villages as well as towns, and Thong is covered. Photos of the system and directions to the site help us plan the visit.
What do you do with what you remove?
We take it away at the end of the visit. While we work, it’s kept contained so the area stays clean.
How do you protect the area?
By covering it before any work starts. We keep the work contained and leave the area clean.
How long does an AHU clean take?
Cleaning takes one overnight shift for many single units, with bigger plant phased. Large plant can be split over several shifts, so call us on 0345 646 2711, or email photos to talk it through.
Can you look after several sites?
Yes. Send the list of sites and the work at each and you will get one fixed quote.
How much notice should we give?
It depends on the time you need and how big the job is. Mention your preferred dates with your enquiry, and if it’s an emergency, call us any time.
Do you look at the system first?
Yes, every time. Diagnosis comes before treatment: the survey shows what needs doing and what access we need and the fixed quote is built on it.
Fixed quotes for AHU cleaning in Thong
The diagnosis comes before the price. We look at:
- How big the system is
- One-off work versus a regular cycle
- The times the site is available
- Any permits to work or inductions
No two sites are the same, so we price each one individually. The size of the job, how we reach it, its condition and the working hours all play a part.
What we need to know
To speed up the quote, send us:
- Any symptoms, from odd noises to smells or leaks
- Photos showing the whole system and its surroundings
- Close-ups of filters, grilles, hatches or access panels
- The times we could work without disrupting the site
Quoting starts with a diagnosis, either from photos and details you send or from a site visit. After that, you get a fixed price for the work so you know the cost before we start.
How it works
Everything the job needs comes with us, from protective sheeting to tools and access equipment. You only need to give us clear access and switch off what needs to be off. On site, the work takes a single shift for a typical unit, longer for large or heavily soiled ones. Visits to a village like Thong are booked in advance, at a time that suits whoever runs the site.
- First the unit is surveyed, from pictures or a visit, and the scope agreed.
- We arrange the shutdown with your staff and sheet the area.
- Filters are dealt with as agreed, and the coils, fan and casing cleaned.
- Drain trays are cleared and cleaned and the outlet checked.
- A TR19® certificate and photo report follow the clean.
Getting ready for the visit
- Mention any sign-in, permit or induction we need
- Make sure someone can let us in and lock up afterwards
- Let us know how we reach the system, including roofs, risers and plant rooms
How to get a quote
To get a fixed quote, phone us on 0345 646 2711 or email us and tell us the type of site, your opening hours and roughly what the system looks like. A few pictures and your last certificate or report help a lot. You’ll normally have a quote within one working day.