Surrey · Air handling unit cleaning
South Merstham AHU cleaning
Looking for AHU cleaning in South Merstham? We survey first, give you a fixed quote and work around your opening hours, then sign off with a report and pictures.
- Leaves and litter drawn into the unit
- Coils clogged with dust and debris
- Rooms that smell stuffy when the system runs
About our AHU cleaning in South Merstham
An air handling unit is the heart of a building’s ventilation: it draws air in, filters it, heats or cools it and pushes it round the ductwork. Whatever builds up inside it travels with that air, so cleaning the unit matters as much as cleaning the ducts. If you are dealing with dust-coated heating and cooling coils and dust built up on fan impellers, we can put it right.
For a building near South Merstham, the visit is planned around how it’s used, and the journey is planned ahead. The method does not change: inspect first, clean, then record what was done.
The sign-off is always in writing: a written report, dated and illustrated with pictures, and for TR19® Grease cleans, a certificate issued through the BESCA VHE portal. Any parts we couldn’t reach are recorded on it too.
- Place
- South Merstham (RH1)
- Region
- Surrey
- Paperwork
- Written report with pictures
- Quote
- Fixed quote, typically within a working day
- Hours
- Evenings, overnight and weekends; 24/7 emergencies
- Call
- 0345 646 2711
- Page updated
- 30 October 2026
Between visits
Good habits slow the build-up between visits. A few tips:
- Note any water around the unit or leaks below it
- Store the TR19 paperwork where auditors can find it
- Stick to the filter change plan
- Keep the area around the fresh air intake clear
Stick to the filter change schedule, as that does more than anything to keep the unit clean. Record each change in the maintenance log.
Do not let leaves, litter or stored materials build up near the fresh air intake. What’s near the intake ends up in the unit.
How it works
We start by comparing what we find with the survey or your photos. Anything unexpected is raised with you before we go further. After that, the work takes anything from half a day for one small unit to several shifts for a plant room full of them. Your opening hours decide when we come to South Merstham, not ours.
- We survey the unit from photos or on site and agree what’s included.
- We arrange the shutdown with your staff and sheet the area.
- Filters, coils, fan section and casing are cleaned in turn.
- Drain trays are cleared and cleaned and the outlet checked.
- A TR19® certificate and photo report follow the clean.
Preparing for the visit
- Arrange a key holder or contact on site
- Let us know about parking and loading
- Plan for cooking equipment or plant to be off before we arrive
Getting a quote
Photos are the quickest way to a quote: the system from a couple of angles, plus any access panels or hatches. Tell us what kind of site it is and when it’s open, and many jobs can be priced from that alone.
Read more
When to call us in South Merstham
No filter stops everything. What gets through settles on coils, fans and the inside of the casing, building up layer by layer.
The symptoms we are asked about most are:
- Drain trays holding standing water
- Coils clogged with dust and debris
- Air handling units never cleaned inside
- Air handling units with blocked filters
Healthcare ventilation, from large hospitals like St Lawrence's Hospital (about 2.8 miles north-east) to small clinics, depends on clean filters, coils and ducts.
Before you book anyone
- Whether the whole system is included, or only the parts that are easy to reach
- Whether inaccessible sections are listed on the report
- Their accreditations, such as BESCA Vent Hygiene Elite, CHAS or SafeContractor
- Whether the figure could change on the day
How we price AHU cleaning
Some jobs are bigger than they look, and some smaller. What affects the quote:
- How big the system is
- Whether it’s a one-off visit or part of a schedule
- How many systems or sites are involved
- Site requirements such as sign-in and permits
What you pay depends on the size of the system, the condition it’s in and how easy it is to reach. We give you a fixed price before we start, so there are no surprises.
What to send for a quote
To speed up the quote, send us:
- Problems your staff have spotted
- Your last certificate, test record or report
- When the site is open and when it’s quiet
- The postcode and the type of business
If you need AHU cleaning in South Merstham, phone us on 0345 646 2711 or send us an email. Tell us what kind of premises it is and when it’s open, plus photos or the previous report if they’re to hand. We typically send a fixed quote within one working day.
Why deal with it now?
Dirty coils and fans make the unit strain to move the same air. That means more wear on the motor and rooms that feel less fresh, and a planned clean is far less disruptive than a breakdown. A site near South Merstham that has to close at short notice is hard to cover for.
Putting the work off seldom saves money. Problems in a system tend to grow, which can make the next visit longer. If you’re unsure, call 0345 646 2711 or email us for straight advice and a fixed quote.
Why choose Duct Doctor in South Merstham
- Trading since 2009
- Full insurance on every job
- Accredited under CHAS and SafeContractor, with ISO 9001
- Evenings, overnight and weekends, plus 24/7 emergency callout
In-house cleaning or a specialist?
If your staff spot something between visits, like drips, unusual noise, smells or damaged filters, it’s best reported rather than tackled in-house. We can diagnose it and quote.
Away from the kitchen, the in-house job is mainly checking: clear grilles, a log of filter changes and reporting anything odd. Cleaning inside ducts and units is specialist work.
Common questions in South Merstham
Can you get to a site in South Merstham?
Yes, smaller places are covered as well as towns. Let us know about access, parking and anything unusual about getting there when you book.
Can you come to South Merstham after we close?
Yes, evening, overnight and weekend work is normal for us. Your customers, staff or residents in South Merstham needn’t be disturbed. Tell us your opening hours when you ask for a quote.
How often do AHUs need cleaning?
It depends on the unit, the filters and how the building is used. Regular inspection shows when it’s due, and we will suggest an interval after the first clean.
Do you have insurance?
Yes. Full insurance covers our work and have been trading since 2009.
Do you look at the system first?
Yes. For many sites, pictures and a few details are enough, and larger or hidden systems get a visit.
How long does an AHU clean take?
It takes half a day to a full day per unit, with large plant planned over several shifts. Size, layout and how dirty it is decide the rest, and we will confirm the time when we quote.
Is there a report after cleaning?
Yes, a TR19® certificate and a photo report. The report also suggests when the unit should next be inspected.
Do you offer emergency callouts?
Yes, any time. For anything urgent, such as a fan failure or damage after a fire, ring the 24/7 line, and we’ll advise on what to do next.
Nearby places to South Merstham
Other services in South Merstham
Multi-site and managed buildings
Facilities teams in offices, schools and healthcare sites book us too across Surrey. Work can be phased by floor, building or site around the people who use them.
Under the Regulatory Reform (Fire Safety) Order 2005, the responsible person must assess and reduce fire risk, and that can be the employer, the owner, a landlord, a facilities manager or a managing agent. Where responsibility is shared, records matter even more.
South Merstham buildings and their air
Food Standards Agency records list about 4 schools, colleges and universities and about 7 hospitals, care homes and childcare premises registered as food businesses across South Merstham 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. South Merstham, about 17 miles from central London, is within our usual area. The visit is fixed around your opening hours, not ours. About 2.8 miles north-east of South Merstham is St Lawrence's Hospital, the nearest hospital. If you run a surgery, clinic or care home, your ventilation deserves the same care as a hospital’s, on a smaller scale.
Classrooms and halls at schools such as Merstham Primary School are easiest to work in when pupils are away. If you manage offices or shops near Merstham station, their ventilation can be inspected and cleaned out of hours.
South Merstham is about 2 miles north-east of Redhill, in Surrey. Wherever you are in the RH1 postcode area, we can carry out AHU cleaning at your premises. South Merstham is one of 395 places in Surrey where we work for AHU cleaning. London is in our area too, around 17 miles away.
Postcode districts we cover here for AHU cleaning: RH1. Whether your site is on Station Road South, London Road South and Station Road or anywhere close by, our technicians can take on the work. We also cover Merstham (1 mile north), Holmethorpe (1 mile south-west), Gatton (1 mile west), Nutfield (2 miles south-east) and Redhill (2 miles south-west). Further out, we also cover Epsom (7 miles north-west), Horley (6 miles south), Ewell (8 miles north-west), Reigate (3 miles south-west), Walton-on-Thames (14 miles north-west) and Caterham (3 miles north-east).
Local landmarks in South Merstham
In South Merstham, that means kitchens and buildings near Merstham Park School, Nutfield Marshes and East Surrey College. There’s a railway station in South Merstham itself: Merstham station. Well-known places in the area include Bletchingley Castle (2.3 miles south-east) and The Belfry (1.7 miles south-west). Open spaces near South Merstham include Colley Hill and Mercers Lake.