A one-off domestic service, booked in spring, is often a low-hundreds illustration in 2026 for a single split: filters, coils, drains, a look at electrics and a report. A heatwave callout for the same unit that has stopped is a different bill: attendance at a premium, then parts, with a wait because every van is busy. A contract can bundle a visit and a clearer response path. Read the exclusions. Refrigerant, compressors and scaffold are often extra. F-gas rules still decide who may handle gas. The company that answers in July is worth more than a badge serviced by a stranger.
A spring visit against an August queue
Planned servicing cleans the parts that make the unit efficient and catches a blocked condensate tray before it stains a ceiling. It is also when an engineer sees a dying capacitor or a perished lagging in March rather than in a panic. For a straightforward house split, budget a low-hundreds illustration per visit. A multi-split or a small shop is more, because there are more coils and a roof to reach. A contract might be similar money to one visit, or a step up into the high hundreds for a domestic multi, in exchange for a diary date and a stated response. Cheap contracts that are only a filter wash and a phone number with no labour included are a product to read twice. Often a domestic service is a low-hundreds illustration in 2026 for one straightforward split. Access, extra indoors and commercial plant cost more.
Attendance, parts and who may touch the gas
Breakdown attendance on a normal weekday might still be a low-hundreds call, waived in part if you proceed, depending on the firm. Evenings, weekends and the second week of a heatwave are when the price and the delay rise. Parts then sit on top. A failed pump or fan can be a small part. A failed compressor on an old R410A unit can turn into a replacement conversation. As a 2026 illustration, one emergency visit plus a simple part can exceed a year of planned service, and you have still had a hot week. That is the case for a contract if you rely on the room: a bedroom every night, a shop that cannot close, a care home lounge. For a spare room used twice a year, a one-off pre-summer check can be enough. Topping up gas is not a service extra you buy off a shelf. If refrigerant is low, it has leaked. A certified engineer should find and repair the leak rather than endlessly recharge. Many small domestic charges sit below mandatory leak-check thresholds, and the work on the circuit is still F-gas work. Commercial plant over the charge thresholds has formal leak-check duties. GOV.UK inspection rules for systems over 12 kW are not the same as a maintenance contract. You can need both. Energy Saving Trust's heat pump pages are a reminder that a dirty air-to-air unit costs you twice: comfort and electricity. Hire the firm that will still come when the logo's helpline is a queue.
Frequently asked questions
Is a service contract always cheaper?
Not on a system you barely use. On a home or a shop that would hurt if it failed in a heatwave, a planned visit and a response promise usually beat one panicked callout.
How much is a domestic service?
Often a low-hundreds illustration in 2026 for one straightforward split. Access, extra indoors and commercial plant cost more. Get a figure for your own kit.
Does the contract include refrigerant?
Often no. Leak repair and recharge are skilled, regulated work and are commonly excluded or capped. Read that line before you sign.
What should a contract say is included?
Ask about coils, the drain, and both the indoor and outdoor units. Ask what is excluded: gas, compressors, access equipment. Priority response should say hours, not a vague promise to come when they can.
Is a heatwave callout the same bill as a spring service?
No. Attendance at evenings, weekends and the second week of a heatwave costs more and takes longer. One emergency visit plus a simple part can exceed a year of planned service, and you have still had a hot week.
Is an inspection the same as a maintenance contract?
No. GOV.UK inspection rules for systems over 12 kW are not a maintenance contract. You can need both. The inspection does not by itself clean the coil.
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How this guide was prepared
This guide was written by the Local AC Installers Editorial Team. We compare official guidance, legislation and established consumer information, separate general information from project-specific advice, and show publication dates and sources. We do not accept installer accreditation claims at face value.