For the first time on record, temperatures exceeded 40 degrees last month, with the Met Office issuing a ‘red extreme heat warning’ meaning it can cause adverse health effects.

Temperatures are on the up this week too, and with Brits told to expect higher temperatures and heatwaves in the future, many people may be considering installing an air con unit at home, particularly if they work from their property rather than a business premise.

But it can set you back by thousands of pounds – a big expense during the cost-of-living crisis and for equipment which is only used for a few short months of the year.

So, if you buy an air con unit and pay for installation in your home office, can you get a tax break on the expense?

Unfortunately not, says HMRC. No part of the installation would qualify for tax relief, regardless of the requirement to work from home.

It wouldn’t satisfy the test that requires expenses to be wholly, exclusively and necessarily incurred in the performance of an employee’s duties.

A spokesperson, said: “Employees who are eligible to claim tax relief for the additional costs of working from home can only claim for things to do with their work, such as business phone calls and gas and electricity for the work area.

“They cannot claim for things that would be used for both private and business use such as broadband or air conditioning units.”

Stuart Crook, partner at accountancy firm, Wellers, said: “The issue with claiming business expenses for things such as installing air conditioning to a home, is that any installation is unlikely to satisfy the wholly and exclusively test. As working from home doesn’t necessarily make a property a business premises, the air conditioning is unlikely to be considered a business asset. This is because the home will benefit from the installation at all times, not just when working.”

However Crook added: “Some dedicated and segregated home offices may be able to use the capital allowance treatment to claim back the cost on expenses. But bespoke advice should always be sought to prevent problems with HMRC.”