How Much Should an AC Unit Cost to Install?

If you are considering air conditioning for your home, one of the first things you want to know is what a fair installation cost looks like. With UK summers becoming hotter and demand for air conditioning increasing, installation prices can vary widely depending on the property, the system, and the installer.

So how much should you expect to pay for an AC unit installation, and what factors separate a fair price from an inflated one?

Why Prices Vary So Much

Air conditioning is not a one-size-fits-all product. The cost depends on:

• The type of unit (split, multi split, ducted)
• The size of the room or property
• The complexity of the installation
• Location and access for engineers
• Whether permissions are required (common for flats and leasehold properties)

This is why quotes from different installers can sometimes look very different.

Typical Installation Costs

For most homeowners across Hampshire, Surrey, Berkshire, and Oxfordshire, here are the price ranges you should expect:

• Single split system: £1,500 to £2,500 installed. Best for cooling a bedroom, lounge, or office.
• Multi split system (2–3 rooms): £3,000 to £5,000 installed. A cost effective choice for larger flats or small houses.
• Whole home system with zoning: £6,000 upwards. Suitable for larger houses in areas like Winchester or Guildford.

If a quote is far lower than these ranges, it is worth checking whether the units are correctly sized or whether the installer is F-Gas certified.

Examples from Real Installations

• A two-bed flat in Reading had a single split system fitted in the lounge for £2,100.
• A detached property in Basingstoke had a multi split across three rooms at £4,500.
• In Oxford, a larger four-room system cost £7,000 due to additional planning requirements.

These figures reflect current market averages across southern England.

What’s Included in a Fair Price

When comparing quotes, it is important to check what is included. A fair installation cost should cover:

• Supply of the AC units (indoor and outdoor)
• Installation by F-Gas certified engineers
• Pipework and electrical work
• System commissioning and testing
• Warranty on both equipment and labour

Additional services such as removing old equipment or applying for planning permission may appear as extra charges.

Running Costs Compared with Installation

While installation is the main upfront cost, running costs are surprisingly affordable. Based on Ofgem’s 2025 average electricity price of 28p per kWh:

• A 2.5kW bedroom unit costs around 20p per hour to run
• A 5kW living room unit costs around 40p per hour
• Using an AC unit for three hours in the evening might cost about £1

These figures highlight the long-term value of professional installation, as a well-sized system is both efficient and cost effective.

Key Things to Watch Out For

When reviewing quotes, avoid simply choosing the cheapest. Some installers may reduce the specification or quote smaller units that are not suitable for the space. This can lead to higher running costs and poor performance.

A fair price should:

• Match the size of the unit to your property
• Be based on reputable manufacturers such as Mitsubishi Electric or Daikin
• Include all necessary installation work and testing
• Provide a warranty for peace of mind

Why Professional Installation Pays Off

Professional installation ensures that your AC system is not only safe but also efficient and long lasting. Poor installations can void manufacturer warranties and cost more in the long term.

At ClimateWorks, we provide transparent quotes for homeowners across Basingstoke, Guildford, Reading, Oxford, and beyond. We make sure the system is sized correctly, installed to regulation standards, and supported with aftercare.

References

• UK Planning Portal
• Ofgem – Energy Price Data
• Energy Saving Trust – Cooling Guidance

Author Bio

Dr Julian Carter is Technical and Compliance Director at ClimateWorks. With over 25 years of experience in air conditioning, refrigeration, and ventilation, Julian advises on compliance with UK building regulations and sustainable system design. He has worked on hundreds of installations across Hampshire, Surrey, Berkshire, and Oxfordshire. Julian is also a visiting professor at a UK university where he teaches building services engineering and energy efficiency.

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