Greater London · Air handling unit cleaning
Air handling unit cleaning in Bishopsgate, Greater London
We cover Bishopsgate for cleaning of air handling units, including filters, coils, drain trays, fans and internal surfaces. Fixed quotes, work around your opening hours and photo reports as standard.
- Debris and leaves in the fresh air intake
- Filters that are clogged or overdue
- Units that have only ever had filter changes
The process
We turn up at the time agreed with you, often in the evening, overnight or at the weekend so the site keeps working. Anything that needs to be off for the work is switched off and left to cool before any work starts, and the area around the work is covered and protected. The work itself takes one overnight shift for many single units, with bigger plant phased. A name and number for whoever controls access to the building in Bishopsgate saves time on the night.
- First the unit is surveyed, from pictures or a visit, and the scope agreed.
- With your site team, the unit is switched off and isolated, then the area around it protected.
- Filters, coils, fan section and casing are cleaned in turn.
- We clean out the drain tray and make sure it drains.
- You get a TR19® certificate and a photo report.
Preparing for the visit
- Clear the space around the work
- Let us know how we reach the system, including roofs, risers and plant rooms
- Tell us the best time to work, such as after service or at a weekend
Ask for a quote
Photos are enough for some jobs, while others need a look on site. Big or complicated sites, and systems that are hard to see in photos, get a survey first. Either way, you get a fixed price before work begins.
Advice
How we handle AHU cleaning in Bishopsgate
Every supply and extract system relies on the air handling unit at its centre: it draws air in, filters it, heats or cools it and pushes it round the ductwork. Anything that collects inside the unit can end up in the rooms it serves, which is why we clean the unit itself, not just the ducts. We are often asked to deal with units that have only ever had filter changes and stale or musty smells from the ventilation, across supply and extract fans, filter sections and internal panels.
Many London buildings have had their ventilation extended and altered through several fit-outs, leaving sections that are hard to reach and seldom cleaned. In Bishopsgate, as elsewhere, cleaning starts with an inspection of what’s there.
The paperwork matters as much as the work. You get a written report with pictures after every visit, covering the work done, any areas we couldn’t access and a recommended next date. File it in your maintenance log so it’s ready for an insurer, fire officer or EHO.
- Location
- Bishopsgate (E1, EC2A, EC1Y)
- Region
- Greater London
- Paperwork
- Photo report after each visit
- Price
- A fixed quote up front
- Working hours
- After hours by arrangement; emergencies any time
- Call
- 0345 646 2711
- Reviewed
- 30 October 2026
Questions from Bishopsgate
Does London parking affect a job in Bishopsgate?
We plan it in advance, so let us know about loading bays, permits and access rules at the building. Much of our London work is done overnight, which helps.
Can a school’s ventilation in Bishopsgate be done out of term time?
Yes. Half-terms and the summer break are the natural time for school work. With about 96 schools and colleges on the FSA’s register within roughly a mile and a half of Bishopsgate, it pays to plan holiday dates ahead. You can call us on 0345 646 2711, or email photos with the dates the site is empty.
Does the AHU have to be shut down for cleaning?
Yes. The unit has to be shut down and isolated before it’s opened. The shutdown is planned with whoever runs the building.
Is there a report after cleaning?
Yes. You receive a certificate and a report showing each section before and after, including anything we think needs attention.
Can you clean the AHU out of hours?
Yes. Evening, overnight and weekend work is all possible, so the building keeps running in the day.
Is a quote from photos possible?
In many cases, yes. Photos of the system and the access, plus your opening hours and last report, are often enough. Where we can’t see enough, we arrange a survey.
Do you have a 24/7 line?
Yes. If something urgent happens, like a fan failing or damage after a fire, call our 24/7 line, and we will advise on what to do next.
Are you accredited?
We hold CHAS, SafeContractor and ISO 9001, and we are a BESCA Vent Hygiene Elite member, cleaning to BESA TR19® Grease. Vent Hygiene Elite is run by BESCA and independently audited.
Why it’s worth doing now in Bishopsgate
A clean unit feeds cleaner air into the ductwork, so the ducts and grilles stay cleaner between cleans. It also means the next inspection has less to find. Planning ahead in Bishopsgate lets you pick a quiet night rather than lose a busy one.
Several systems or sites on one quote can make for a more efficient booking. Tell us about everything you’d like looked at, and you will get one fixed quote.
Why choose Duct Doctor in Bishopsgate
- Ventilation hygiene specialists since 2009
- Accredited under CHAS and SafeContractor, with ISO 9001
- A written report with photos after every visit
- One contact for all your sites in London and the South East
What the work involves, part by part
Filters
Filters are the first line of defence in the unit. We check them, and clean or change them as agreed in the quote, and the housing around them is cleaned too.
Drain trays
Older trays can corrode and start leaking. Their condition goes into the report with pictures so you can decide on any repairs.
What a clean will not put right
In fairness, there are a few things this work will not fix:
- Building management system faults
- Ventilation that was badly designed in the first place
- Mechanical faults with motors, belts or bearings
If in doubt, ring 0345 646 2711 or email us and we’ll say what we think.
What the work covers
- Filter sections
- Drain trays
- Dampers and louvres
- Heating and cooling coils
- Internal panels
- Supply and extract fans
Nearby places to Bishopsgate
What else we do in Bishopsgate
How we price AHU cleaning
Sites vary more than people expect. What affects the quote:
- Any permits to work or inductions
- What state the system is in
- How many systems or sites are involved
- The size of the system
We do not list prices on the website, because each job is priced on what it involves. For a fixed quote, call 0345 646 2711 or use the quote form, and we’ll explain what it covers.
What we need to know
What to send for a quote:
- Any symptoms, from odd noises to smells or leaks
- The site address and the type of premises
- The paperwork from the last visit, if you have it
- Where the plant sits or the system leaves the building, such as a roof or outside wall
There’s no standard price list, because every site is different. Instead, we look at your site first, from photos or a survey, then send a fixed quote. To get going, call us on 0345 646 2711 or email us.
In-house cleaning or a specialist?
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, next to our reports.
In-house cleaning and specialist cleaning do different jobs. A daily filter wipe and a weekly filter wash keep grease down at the front of the system, but grease that has passed the filters is out of reach. That part needs specialist access and equipment.
What AHU cleaning looks like in Bishopsgate
Food Standards Agency records list about 96 schools, colleges and universities, about 65 hospitals, care homes and childcare premises and about 88 hotels, B&Bs and guest houses registered as food businesses within 1.5 miles or so of the middle of Bishopsgate. Buildings like these often rely on mechanical ventilation, which TR19® Air covers. Bishopsgate’s nearest hospital, London Bridge Hospital, is about 0.7 miles south. Clean air matters most where people are unwell, and that’s as true in a care home as in a hospital. London plant rooms are often on roofs or in basements reached through occupied floors.
London Bridge Hospital, about 0.7 miles south, is the nearest hospital to Bishopsgate, and healthcare sites of every size need their supply air kept clean. Classrooms and halls at schools such as The London School of Barbering are easiest to work in when pupils are away.
Bishopsgate is about 1 mile north-east of London, in Greater London. From the centre of Bishopsgate to the outskirts, AHU cleaning is available to all kinds of commercial premises, from a single unit to a large public building. We cover 764 places across Greater London, large and small.
Work in E1, EC2A and EC1Y is surveyed, quoted and booked the same way as anywhere else. Streets in the area include Bush Lane, Swan Lane and Love Lane, and we cover them all for AHU cleaning. You’ll find Bishopsgate on the A3 and A10, which makes it straightforward for our technicians to reach for AHU cleaning. Other places close to Bishopsgate include Aldgate (1 mile south-east), Spitalfields (1 mile east), City of London (1 mile west), Tower Hill (1 mile south) and Whitechapel (1 mile east). Within a short drive, we also cover City of Westminster (3 miles west), Marylebone (3 miles west), Kensington (5 miles west), Walthamstow (5 miles north-east), Hampstead (5 miles north-west) and Ruislip (15 miles west).
Landmarks near Bishopsgate
In Bishopsgate, that means kitchens and buildings near Bishopsgate Institute Special Collections and Archives, St Mary-at-Hill and The Aldgate School. You will also find White Hart pub (under half a mile north-east), Central Foundation Boys' School (0.7 miles north) and Finsbury Circus (under half a mile north-west). There’s a railway station in Bishopsgate itself: London Liverpool Street station. Nearby you’ll also find London Bridge Hospital (0.7 miles south) and Gabriel's Wharf (1.2 miles south-west). The countryside around Bishopsgate includes St. James's Park Lake and Tower Hill.
What we’re called out for in Bishopsgate
Whatever surrounds a building in Bishopsgate, the air drawn into its AHU carries dust, pollen and debris. Most of it lands at the intake and the first stage of filters, and the finer material travels on.
What we are most often called out for:
- Filters that are clogged or overdue
- Intake sections clogged with outdoor debris
- Units that have only ever had filter changes
- Blocked condensate drains and slimy trays
If you manage offices or shops near London Liverpool Street station, their ventilation can be inspected and cleaned out of hours.
What your quote should include
- Which accreditations they hold, and whether you can check them
- Whether the figure could change on the day
- Whether a written report and pictures are included
- Whether the quote is based on a survey or photos