How to choose an air conditioning installer in the UK

Picking the right installer matters more than picking the right unit. Here’s the honest checklist we’d run through with a friend before they hand anyone a deposit.

The one certification that isn’t optional: F-Gas

Air conditioning runs on refrigerant, and by law anyone who installs or handles refrigerant in the UK must be F-Gas certified — with the company REFCOM registered. This isn’t a nice-to-have or a badge for the website; it’s a legal requirement. No F-Gas certification means you walk away, full stop. Separately, the electrical work often counts as notifiable under Part P of the Building Regulations, so the new circuit should be certified. You’ll also see MCS mentioned — that mainly matters for grant-eligible heat pumps (like air-to-water systems), and much less for a straightforward air conditioning install, so don’t let anyone use its absence to justify a higher price on a standard job. Our guide on what to expect from an installation covers the paperwork you should end up with.

The questions to ask before you commit

A good installer will answer all of these without flinching. If any question makes them awkward, that tells you something.

• Are you F-Gas certified, and can I see it? (A genuine one will show you without being asked twice.)
• Is the quote itemised — units, indoor and outdoor, pipe runs, electrical work, and making good?
• What’s the warranty, on the unit and on the workmanship — and does it depend on annual servicing?
• Will you handle the building and planning checks, or is that on me?
• Do you carry public liability insurance?
• Can I see recent installs near me, or a few local reviews?

Red flags worth walking away from

Most bad experiences share the same early warning signs. Be wary of pressure to sign today, cash-only pricing, “no need to see the units first,” or a quote handed over with no proper site survey. A refusal to put anything in writing, or a deposit that feels far too large, both point the same way. Good installers are calm about all of this — they expect you to compare, and they know a written quote protects them as much as you. Our cost guide shows the ranges to sanity-check a number against, and the brands guide helps you tell a serious unit spec from a vague one.

Why five quotes is a trap

Common advice says get five quotes. In practice that means five surveys, five sales pitches, five firms all knowing they’re in a bidding war — which pushes everyone toward the cheapest corners rather than the best job. It’s the same problem with the shared-lead sites and directories: your details get sold to several companies at once, and you spend the next week fielding calls. What you actually want is one good, vetted firm who’ll do the job properly, not a race to the bottom. It’s exactly why we match each homeowner to a single vetted installer rather than selling the enquiry on — one honest option, not the only way to do it, but it saves the scrum. You can see the standards we hold installers to in our installer terms.

Get it in writing

Whoever you choose, the golden rule is simple: everything that matters — the equipment, the price, the warranty, what’s included and what isn’t — goes in writing before any money changes hands. A good installer will offer that as a matter of course. If you’d like us to match you with one vetted, F-Gas certified installer for your area, tell us a little about your home below.