Frequently asked questions

A single wall-mounted split typically costs £1,450–£2,950 plus VAT installed, a ceiling cassette £2,150–£4,950 per unit, and a VRF system £2,450–£4,950 per indoor unit. A small shop or office with two to four indoor units typically comes to £4,950–£16,500 plus VAT.

Yes, for new installations and replacements on the UK mainland. Remote and island locations carry a travel charge, quoted in writing first. Service, repair and inspection visits are priced before we book them.

A service visit typically costs £175–£245 plus VAT for the first indoor unit, with additional indoor units around £85–£145 each on the same visit, so a two-unit system is usually £175–£390.

Typically £195–£495 per indoor unit per year for two visits, plus VAT. Quarterly contracts for kitchens or server rooms cost more.

Prices on this site are guides. Your price is fixed in a written quote after a survey or before a visit, and anything extra is agreed with you first.

A single split system is usually fitted in a day. A small office or shop with three or four units typically takes two to four days, and a VRF system for a whole floor can take several weeks. We confirm the programme in the quote.

It depends on where the outdoor unit goes and the building. Units on a rear flat roof are often straightforward; front elevations, conservation areas and listed buildings usually need consent. We flag this at survey.

As a rough guide, offices need about 80–125 W of cooling per square metre, more with lots of glazing, dense occupancy or IT. A heat load survey gives the real figure for each zone.

Cassettes suit offices with a suspended ceiling and spread air evenly in four directions. Wall units are cheaper and suit small rooms or solid ceilings. Ducted units are the most discreet.

Usually once you need more than about six to eight indoor units, want central control, or are short of space for outdoor units. One outdoor unit can replace many.

In Great Britain, new single split systems holding less than 3 kg of refrigerant cannot use a refrigerant with a global warming potential of 750 or more, so most are now R32. Larger systems may use R32, R454B or R410A depending on the equipment. We state the refrigerant and charge in the quote.

At least once a year, and every three to six months for systems in kitchens, gyms, salons, dusty environments or server rooms that run 24/7.

Common causes are blocked filters, a dirty outdoor coil, a refrigerant leak, a failed fan or a controls fault. A diagnostic visit finds the cause.

Usually a blocked condensate drain or a failed condensate pump. Switch the unit off to avoid ceiling damage and book a repair.

A musty smell usually comes from mould or bacteria in the coil, tray or drain. A deep clean and drain treatment normally removes it.

No — you can keep running an R22 system, but it cannot be maintained with virgin or recycled R22, so most repairs involving the refrigerant circuit are no longer possible.

In Great Britain, equipment containing F-gas at or above 5 tonnes CO2 equivalent (with exemptions for some hermetically sealed equipment below 10 tonnes). Many VRF and larger split systems qualify.

At least every 12 months from 5 tonnes CO2e, every 6 months from 50 tonnes, and every 3 months from 500 tonnes. Where automatic leak detection is fitted, each interval doubles to 24, 12 and 6 months.

The operator of the equipment — normally the business with control over it. Contractors do the checks; the operator must make sure they happen and keep records.

In England, Wales and Northern Ireland, yes if the air conditioning you control in a building adds up to more than 12 kW of effective rated output, at least every five years. In Scotland, systems of 12 kW or more need inspecting (separate units count together only where centrally controlled), at intervals set by the accredited expert.

In England and Wales a £300 penalty can be issued for failing to have a valid report, enforced by local Trading Standards. Northern Ireland also sets a £300 penalty.

Commercial Air Conditioning is a trading name of S&K Property Investments and Improvement Ltd (company number 16932889), part of the S&K Group, based in Great Barr, Birmingham.

Yes. We work across England, Scotland, Wales and Northern Ireland. Remote island and Highland locations are covered by arrangement, with travel agreed before any visit.

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