Running & maintenance
Owning a system well: running costs, servicing, cleaning, troubleshooting and getting the best efficiency.
Running your air conditioning cheaply and reliably
Once a system is fitted, the cost and reliability come down to how you run and look after it. This is the place to understand what air conditioning actually costs to run, how to keep it efficient, and the small amount of maintenance that keeps it working well for years.
Running cost is the question most people ask, and the honest answer is that it depends on the unit and how long you leave it on. At the Ofgem price cap of 26.32p per kWh for October to December 2026, a typical unit costs roughly 13p to 53p per hour to run. Our guide to what air conditioning costs to run breaks that down so you can work out a realistic figure for your own home.
A little upkeep goes a long way. Cleaning or replacing the filters and keeping the outdoor unit clear is simple and makes a real difference to efficiency. A professional service is commonly recommended once a year and is roughly £80 to £150. The refrigerant is sealed, so it does not need routine topping up unless there is a leak. Our guide to how often it should be serviced explains what a service covers and when to book one.
Small habits keep costs down: setting a sensible temperature rather than the coldest, using timers, closing doors and blinds against the sun, and letting the unit hold a steady temperature instead of blasting cold air. The guides below are here to help you run your system cheaply and keep it reliable, without spending more than you need to.
Running & maintenance guides
Heat pump servicing and winter maintenance for air-to-air units: what to check, what it costs, and common winter faults
A wall split used for heating needs one professional service a year, ideally before the cold arrives, at £60 to £150 per unit. Here is the checklist you can do yourself, what the engineer does, and how to tell normal frost from a real fault.
1 Sep 2026
The most efficient way to run an air-to-air heat pump in winter
Ten settings and habits that change what your wall split costs to heat with, ranked by impact, plus the honest answer on leaving it on all day and a worked monthly example.
28 Aug 2026
Using your air conditioning for heating: cost per hour, the right settings, and what to expect
A modern wall split heats a room for 14p to 23p an hour, a third of what a fan heater costs. Here is the maths, the settings that matter, and what happens when it gets cold.
14 Aug 2026
Why is my air conditioner not cooling? Causes and fixes
A UK troubleshooting guide for a home unit that has stopped cooling: the common causes in order, the DIY fixes that cost nothing, and when to call an engineer.
13 Jul 2026
Air conditioning maintenance: a UK home upkeep guide
Most air conditioning maintenance is simple DIY. Here is how to clean the filters, indoor and outdoor units, drains and portables, and where the F-Gas line falls.
6 Jul 2026
Is air conditioning expensive to run? UK running costs explained
Honest, dated running costs for home air conditioning, from pence per hour to a full summer. See the maths, the by-size table, and why AC heating can beat gas.
20 Jun 2026
How often should air conditioning be serviced?
A professional service once a year is the UK norm for home air conditioning, with simple filter cleaning by you in between. Here is what a service covers, what it costs, and what you can safely do yourself.
11 Jun 2026Running and maintenance: common questions
How much does air conditioning cost to run? +
It depends on the size of the unit and how long you run it. At the Ofgem price cap of 26.32p per kWh for October to December 2026, a typical unit costs roughly 13p to 53p per hour. A modern, efficient unit sized correctly for the room will sit towards the lower end of that range.
How often should air conditioning be serviced? +
An annual service is commonly recommended to keep a system efficient and reliable. A service is roughly £80 to £150, and it covers cleaning, checks and making sure the system is running as it should. Keeping the filters clean between services helps maintain performance.
How can I make my air conditioning cheaper to run? +
Set a sensible target temperature rather than the coldest setting, use timers so it only runs when needed, and close doors and blinds to keep the heat out. Keeping the filters clean and the outdoor unit clear helps the system run efficiently. A correctly sized, modern unit also costs less to run than an old or undersized one working flat out.
Do air conditioners need topping up with refrigerant? +
No, not under normal use. The refrigerant in an air conditioner is sealed in a closed circuit, so it does not need routine topping up. If the system is losing performance and needs refrigerant added, that points to a leak, which should be found and repaired by a qualified engineer.
More guides
To dig into the numbers, our cost guides cover what air conditioning costs to buy and run. Our living with air conditioning guides cover the day-to-day of using a system well, and you can also browse every guide in one place.
Need a service or repair?
Find an F-Gas registered company near you to service or repair your system, or browse units if you are ready to upgrade.