Surrey · Air handling unit cleaning
Dora's Green AHU cleaning
AHU cleaning in Dora's Green from ventilation hygiene specialists trading since 2009. Evenings, overnight and weekends, plus a 24/7 emergency line.
- Coils clogged with dust and debris
- Debris and leaves in the fresh air intake
- Filters that are clogged or overdue
About our AHU cleaning in Dora's Green
A cooling coil drips condensate into a tray that should drain away. If the outlet blocks, standing water and slime build up, right in the path of the air going into the building. Cleaning and clearing it is a key part of the job. Common call-outs are for air handling units with blocked filters and dust-coated heating and cooling coils, across internal panels, dampers and louvres and filter sections.
Rural buildings with mechanical ventilation, such as care homes and country hotels, often keep their units in roof spaces or outbuildings, where filters and drain trays get forgotten.
Duct Doctor has been trading since 2009, as a BESCA Vent Hygiene Elite member, cleaning to BESA TR19® Grease. CHAS, SafeContractor and ISO 9001 are in place too, and we carry full insurance.
- Place
- Dora's Green (GU10)
- Wider area
- Surrey
- Paperwork
- Written report with photos
- Quote
- Fixed quote, normally within a working day
- Hours
- Evenings, overnight and weekends; 24/7 emergencies
- Phone
- 0345 646 2711
- Last updated
- 30 October 2026
How it works
A visit follows the same order every time: protect the area, isolate whatever needs isolating, carry out the AHU cleaning, clear away and leave you the report. On site, the work takes half a day to a full day per unit, with large plant planned over several shifts. Photos of the system and how to reach it help us plan a visit to Dora's Green.
- First we agree when the unit can be switched off, including evenings or weekends.
- We take before pictures of each section of the unit.
- Filters, coils and internal surfaces are cleaned from intake to discharge.
- We finish with the fan section and the drain tray.
- We take after pictures and issue the certificate and report.
Getting ready for the visit
- Let us know how we reach the system, including roofs, risers and plant rooms
- Clear the space around the work
- Name a contact who can let us in at the agreed time
Ask for a quote
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, before we start.
Related advice
Dora's Green: your questions answered
Can you come to Dora's Green after we close?
Yes, out-of-hours work is a big part of what we do. The work in Dora's Green can fit around your hours. Your opening times are the first thing we ask for.
Can you clean school ventilation in Dora's Green during the holidays?
Yes, holiday work suits schools best. With about 3 schools and colleges on the FSA’s register within roughly a mile and a half of Dora's Green, it pays to plan holiday dates ahead. Just phone us on 0345 646 2711, or email photos with your term dates and we’ll plan around them.
How much notice should we give?
Book as early as you can for planned work, especially if the next clean or test is due soon. For emergencies, we take calls 24/7.
Do you offer maintenance contracts?
Yes, of course. Send details of the systems and how they’re used and we will propose a schedule with a fixed quote.
How do you protect the area?
With sheeting and covers, before anything else happens. We keep the work contained and leave the area clean.
What is TR19?
A BESA specification, with two parts that matter most here: TR19® Grease for kitchen extracts and TR19® Air for supply and extract systems. It is not law, but it’s the benchmark.
How often do AHUs need cleaning?
That is set by inspection, in line with TR19® Air. A hard-working unit, or one serving a hospital or care home, may need cleaning more often.
Can you quote from pictures?
In many cases, yes. With good pictures, the site type and your last report, we can price many jobs. Larger or hidden systems need a survey on site first.
What affects the cost of AHU cleaning
We do not publish a price list, because no two systems are the same. The quote depends on:
- What state the system is in
- One-off work versus a regular cycle
- Travel, parking and unloading
- Site rules, permits and inductions
Whatever the type of site, the quote works the same way: the size of the job, access, condition and working hours. Call for a fixed quote and we’ll explain each part.
What to send for a quote
There’s no need for technical detail. It helps if you can send:
- Anything you’ve noticed, such as smells, noise, drips or poor airflow
- Any access panels or hatches you can see
- Wide photos of the system and the area around it
- The roof, plant room or outside wall the system runs to
Want a quote for AHU cleaning? Please call 0345 646 2711 or drop us a line and tell us about the site. We will talk you through the work and give you a fixed quote before you commit to anything.
Part by part
Heating and cooling coils
Heating and cooling coils have tightly packed fins that trap fine dust. They’re cleaned using methods that won’t bend or flatten the fins.
Fans and fan sections
Every bit of air passes the fan, so a dirty fan sends dirt downstream. The impeller, its housing and the fan chamber are cleaned.
What we are called out for in Dora's Green
An overdue filter loads up with dirt, 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.
Most sites get in touch after spotting something like this:
- Fan sections that haven’t been cleaned in years
- Leaves and litter drawn into the unit
- Odours coming through the supply air
- Coils clogged with dust and debris
School buildings such as Crondall Primary School are usually done in the holidays, so classrooms are not disturbed.
What your quote should include
- Proof of accreditation you can verify
- Whether they’re fully insured
- Whether a survey comes first
- How VAT is shown on the quote
Between visits
How long the results last depends on use and care. We suggest:
- Plan the next inspection before the last report gets filed away
- Store the TR19 paperwork where auditors can find it
- Report stiff or damaged access doors
- Note any water around the unit or leaks below it
We recommend when the unit should next be inspected or cleaned, based on what we found. TR19® Air is risk-based, so the interval depends on the unit and how the building is used.
Do not let leaves, litter or stored materials build up near the fresh air intake. Anything around the intake is likely to be drawn in.
Also near Dora's Green
Other services in Dora's Green
What AHU cleaning looks like in Dora's Green
The FSA’s food hygiene register lists about 3 schools, colleges and universities and about 5 caring premises (care homes, nurseries and hospitals) with registered kitchens or food service within 1.5 miles or so of the middle of Dora's Green. Many buildings of this kind have supply and extract ductwork that gathers dust and needs inspecting. Dora's Green is about 37 miles from central London, well within the area we cover across London and the South East. The visit is fixed around your opening hours, not ours. Fleet Community Hospital is the nearest hospital, about 4.1 miles north of Dora's Green. Clean air matters most where people are unwell, and that is as true in a care home as in a hospital.
Healthcare buildings such as Fleet Community Hospital, about 4.1 miles north, depend on their ventilation; if you manage a surgery, clinic or care home near Dora's Green, yours matters too.
Dora's Green is about 2 miles north-west of Farnham, in Surrey. We provide AHU cleaning for commercial premises of every kind in Dora's Green and the rest of Surrey. Our Surrey coverage runs to 395 places, and Dora's Green is one of them. There’s also a page for Guildford, roughly 11 miles from Dora's Green.
Our technicians cover all of the GU10 postcode area for AHU cleaning and the roads nearby. If your site is just outside Dora's Green, we cover Warren Corner (1 mile north), Redlands (1 mile north-west), Ewshot (1 mile north), Dippenhall (1 mile south) and Crondall (1 mile west). We also work in nearby towns such as Guildford (11 miles east), Woking (13 miles north-east), Camberley (9 miles north-east), Frimley (8 miles north-east), Haslemere (11 miles south-east) and Ash (5 miles east).
Around Dora's Green
We work in commercial kitchens and buildings around Weydon School. The closest station to Dora's Green is Farnham station, about 2.3 miles south-east. A little further out are Powderham Castle (1.1 miles south-west) and Museum of Farnham (1.8 miles south-east). For a walk, there’s Aunt's Pool and Farnham Park.
Landlords, agents and facilities managers
Keeping records across a portfolio is half the battle. Every visit ends with a dated report and photos, so you can show an insurer or inspector what was done at each site.
Whether it’s one building or many, you get the same standard: the system surveyed, the price fixed, the visit fitted around trading and everything written up afterwards.
What a clean won’t put right
Before booking, it helps to know what’s not included:
- Mechanical faults with motors, belts or bearings
- Coils that are corroded or leaking and need replacing
- Controls and BMS settings that run the unit
If you’re not sure, just call us on 0345 646 2711 or drop us a line and we’ll give you a straight answer.
What the work covers
- Drain trays
- Heating and cooling coils
- Filter sections
- Dampers and louvres
- Supply and extract fans
- Internal panels