When air conditioning fails in a server room, a restaurant at full service or an office during a heatwave, our featured pick in London is Be Cool Refrigeration: it runs 24/7 emergency callouts, prioritises server rooms, restaurants and other critical spaces for same-day visits, and stocks its vans with common parts and refrigerant to fix most faults in one trip. Other firms have their own strengths. Aspect states a one-hour emergency response, Pimlico Plumbers runs a 24-hour line with a large engineer fleet, The Air Conditioning Company can deliver portable cooling the same day, Hamilton Air Conditioning claims 24/7 support in North London, ADK Kooling keeps an emergency line open 365 days a year, and JP Air Conditioning answers out-of-hours calls in South East London.
Disclosure: This is a sponsored article. Be Cool Refrigeration paid for this placement and appears first as our featured pick. No other company on this list paid to be included, was contacted, or reviewed this article before publication.
How we built this list
We researched these companies on 8 October 2026 using desk research only. We did not test response times.
Who qualified: London-based firms that advertise emergency or out-of-hours air conditioning repair.
What we compared: stated availability (24/7 or office hours), stated response targets, prioritisation of critical sites, parts carried, temporary cooling options and pricing basis.
Sources: each company’s website. Every response time below is a company target, not a measured result.
How we ordered it: Be Cool Refrigeration is first as the sponsored featured pick. The rest are ordered by how specific their emergency commitments are. We did not score them.
At a glance: emergency AC engineers in London
| # | Company | Strongest fit | Main differentiator | Pricing basis | Key consideration |
| 1 | Be Cool Refrigeration (featured, sponsored) | Server rooms, restaurants and offices | 24/7 callouts; critical sites prioritised; stocked vans | Diagnostic fee credited to repair | Same-day subject to engineer availability |
| 2 | Aspect | Anyone needing the fastest stated response | 1-hour emergency response; callback in 15 minutes | From £63 per half-hour + VAT | Generalist; repairs “normally” same-day |
| 3 | Pimlico Plumbers | Homes needing night-time help | 24-hour line, large fleet | Quote before work | No AC certifications named |
| 4 | The Air Conditioning Company | Sites needing temporary cooling | Same-day portable hire | Hire from £39.50 per week + VAT | No repair response time stated |
| 5 | Hamilton Air Conditioning | North London homes and restaurants | 24/7 support claim; any make | Upfront pricing | No response target |
| 6 | ADK Kooling | Commercial kitchens | Emergency line 365 days | Not publicly listed | Office hours weekdays 8 to 6 |
| 7 | JP Air Conditioning | South East London offices | Out-of-hours calls answered | Not publicly listed | Listed hours weekdays 9 to 5 |
Response times and hours are as stated by each company on its own website, checked 8 October 2026.
1. Be Cool Refrigeration | Our featured pick for critical sites that cannot wait for cooling
Overview
Be Cool Refrigeration is a London air conditioning and refrigeration contractor based on Ludgate Hill, EC4, which says it has repaired AC since 2004. It offers 24/7 emergency callouts across Greater London and says server rooms, restaurants and other critical environments are prioritised for same-day attendance.
Its engineers carry common parts, filters and refrigerant on every callout, and repair all major brands including Daikin, Mitsubishi Electric, Samsung, LG, Fujitsu and Toshiba. It also designs server room cooling with high-temperature alarms and redundancy, which can reduce future emergencies.
Key details
- Core offering: 24/7 emergency AC repair, scheduled repairs, server room cooling.
- Coverage: Greater London and inside the M25.
- Customer fit: server rooms, restaurants, offices and homes.
- Pricing and terms: diagnostic fee quoted upfront and credited to the repair; costs confirmed before work; standard repairs typically within 24 to 48 hours.
Where Be Cool Refrigeration stands out
It triages by risk. Be Cool says critical environments are prioritised, so a server room overheating at 2am is treated differently from a bedroom unit, which is what a business wants from an emergency line.
It aims to finish on the first visit. Stocked vans mean common faults such as drain blockages, PCB failures and low refrigerant can be fixed without waiting days for parts.
What to consider
Emergency attendance is same-day “subject to engineer availability”, with no fixed hour target. Ask for an arrival window on the call. The diagnostic fee is not published.
Best fit
Businesses with server rooms, kitchens or occupied offices that need a 24/7 specialist who will triage by risk.
Website: becoolrefrigeration.co.uk
2. Aspect | Best for buyers who want the fastest stated response
Overview
Aspect Maintenance Services Limited, trading as Aspect, is a multi-trade maintenance company based in Chessington, KT9, covering all 32 London boroughs. It states a one-hour response for emergency AC calls, a callback within 15 minutes, and engineers who work evenings and weekends.
Its AC team is licensed for nine brands and holds F-Gas licensing through Refcom. It also repairs commercial refrigeration.
Key details
- Core offering: emergency and scheduled AC repair; commercial refrigeration repair; other trades.
- Coverage: all London boroughs and inside the M25.
- Customer fit: homes, landlords and businesses.
- Pricing and terms: from £63 per half-hour plus VAT, one-hour minimum; no parking or ULEZ charges; 12-month guarantee.
Where Aspect stands out
Its emergency target is the most specific here: a one-hour response with a 15-minute callback.
You know the hourly cost before the engineer arrives, which removes one source of stress in an emergency.
What to consider
Aspect says repair visits are “normally” same-day, with 24 hours as the fallback. Out-of-hours rates are not stated separately; ask whether they differ.
Best fit
Homes and businesses that want a fast stated response and a known hourly rate.
Website: aspect.co.uk
3. Pimlico Plumbers | Best for homeowners needing help at night
Overview
Pimlico Plumbers Ltd is a London multi-trade company with engineers across the capital and a 24-hour line for emergencies. It repairs air conditioning with no power, no cooling or heating, noise, gas leaks or poor performance, and says engineers carry spare parts for most issues.
It also installs and maintains AC and provides plumbing and electrical trades.
Key details
- Core offering: AC repair, maintenance and installation; general trades.
- Coverage: London.
- Customer fit: homeowners and small businesses.
- Pricing and terms: quote before work; rates not published; work guaranteed, duration not stated.
Where Pimlico Plumbers stands out
A 24-hour line staffed by a large firm means someone will answer at night.
It can send other trades if a leaking unit damages a ceiling or trips an electrical circuit.
What to consider
Its “1 hour response” headline is not explained in the page body, no AC certifications are named, and reviews describe it as pricey. Ask for the rate and certificate.
Best fit
Homeowners who want any-hour access and may need other trades on the same visit.
Website: pimlicoplumbers.com
4. The Air Conditioning Company | Best for sites that need temporary cooling straight away
Overview
The Air Conditioning Company, trading name of Airconco UK Ltd, is based in Mill Hill East, NW7, and says it was founded in 1986. It repairs fixed AC across Greater London and the Home Counties and offers same-day portable unit hire in London.
Hire units range from a 2.6kW model at £39.50 per week to a 6.1kW model at £229 per week, both excluding VAT.
Key details
- Core offering: fixed AC repair and maintenance; portable hire and sale.
- Coverage: Greater London and the Home Counties.
- Customer fit: server rooms, offices and events.
- Pricing and terms: repair rates not listed; hire prices published.
Where The Air Conditioning Company stands out
It can keep a room cool while the repair waits. For a server room where a part will take days, same-day portable hire is the practical emergency fix.
Its hire prices are published, so you can budget the stopgap.
What to consider
No repair response time is stated, and the site does not mention 24/7 repair cover.
Best fit
Offices and server rooms that need temporary cooling the same day while a repair is arranged.
Website: airconco.com
5. Hamilton Air Conditioning | Best for North London homes and restaurants
Overview
Hamilton Air Conditioning Ltd, based in Mill Hill, NW7, claims 24/7, seven-day support and 24-hour assistance across London. It repairs any make or model and lists split, ducted, cassette and VRV/VRF systems.
A testimonial on its site describes a restaurant repair in Chelsea.
Key details
- Core offering: AC repair, maintenance, installation and ventilation.
- Coverage: London, North London focus.
- Customer fit: homes and restaurants.
- Pricing and terms: upfront parts and labour pricing; rates not listed.
Where Hamilton Air Conditioning stands out
It commits to quoting before it works, which helps in an emergency when buyers are vulnerable to open-ended bills.
It is close to North London addresses, which can shorten travel in an emergency.
What to consider
No response target, certifications or review counts are published.
Best fit
North London homes and restaurants that want a nearby 24/7 contact and an upfront price.
Website: hamiltonaircon.com
6. ADK Kooling | Best for commercial kitchens with mixed equipment
Overview
ADK Kooling, which names A-D-K Kooling Ltd, repairs air conditioning and commercial refrigeration across Greater London, Kent and Surrey. It says its emergency number is available 365 days a year, while office hours are weekdays 8am to 6pm.
It is F-Gas certified and a VHR member, and offers out-of-hours work.
Key details
- Core offering: AC and refrigeration breakdown repair, PPM, ventilation.
- Coverage: Greater London, Kent and Surrey.
- Customer fit: commercial kitchens and public-sector sites.
- Pricing and terms: not publicly listed.
Where ADK Kooling stands out
One emergency number covers AC and refrigeration, useful when a kitchen loses both cooling and a fridge in a heatwave.
It reaches Kent and Surrey, helpful for groups with sites outside London.
What to consider
No response target is given; it says it works “as quickly as we can”. Two addresses appear on the site.
Best fit
Commercial kitchens in London, Kent and Surrey that want one emergency number for AC and refrigeration.
Website: adk.co.uk
7. JP Air Conditioning | Best for South East London offices already on its books
Overview
JP Air Conditioning, based in Bromley, BR2, offers emergency call-outs and repairs as part of its installation and maintenance service. It says out-of-hours calls are answered, though listed office hours are weekdays 9am to 5pm.
It is a Daikin Business Partner and works on Mitsubishi, Toshiba, Fujitsu and Panasonic systems.
Key details
- Core offering: AC repair, maintenance and installation.
- Coverage: Greater London; South East focus.
- Customer fit: offices and commercial premises.
- Pricing and terms: not publicly listed.
Where JP Air Conditioning stands out
Existing customers have continuity: the engineer who services the system knows its history.
It covers the City and Canary Wharf as well as Bromley.
What to consider
The 24/7 footer claim conflicts with weekday office hours, and no response target is published.
Best fit
South East London offices with JP-installed or JP-serviced systems.
Website: jpaircon.com
What to do when your AC fails
- Note the error code. Engineers can often diagnose from it on the phone.
- Turn off a leaking unit. Protect ceilings and electrics until the engineer arrives.
- For server rooms, act on temperature. Shut down non-critical equipment and consider portable cooling.
- Ask about charges before booking. Call-out, out-of-hours and diagnostic fees vary.
- Ask for an arrival window, not just “same day”.
Frequently asked questions
Can I get an AC engineer at night in London?
Be Cool Refrigeration, Aspect and Pimlico Plumbers advertise 24/7 or 24-hour cover. Ask whether night callouts carry a higher rate.
How fast will an emergency AC engineer arrive?
Aspect states a one-hour emergency response; Be Cool Refrigeration offers same-day emergency callouts subject to availability. These are targets.
What if the part is not available?
Ask about temporary cooling. The Air Conditioning Company hires portable units with same-day delivery in London, from £39.50 per week excluding VAT, checked 8 October 2026.
How can I avoid AC emergencies?
Regular servicing catches blocked drains and refrigerant loss early. For server rooms, a backup unit and high-temperature alarms reduce risk.
The bottom line
For businesses with server rooms, kitchens or occupied offices that need 24/7 specialist cover with risk-based triage, Be Cool Refrigeration is our featured pick. If a stated one-hour response matters most, compare Aspect. If you need temporary cooling while you wait, The Air Conditioning Company’s same-day hire is worth knowing about. Save your chosen firm’s emergency number before the next heatwave.
