The firm, which installs and maintains air conditioning and heat pump systems across the UK, was established on February 13, 1980. Back then, the average wage was £6,000 and a litre of petrol was just 28p.

Petrol prices and salaries have grown somewhat, and so too has Coolair. Originally established above a terraced house in Gorton, the nationwide firm now operates out of three offices; its southern base in Maidstone, Kent; a Midlands office in Cannock and Coolair House, its headquarters in Dukinfield, Manchester.

What remains the same however is the firm’s commitment to its clients, as well as its unique ethos which ensures loyalty among its 80-plus staff.

John Otterson is Coolair Equipment’s chairman and the firm’s longest serving current member of staff, having joined the business in 1984, when it was a mere four years old. He said: “Today’s air-conditioning industry is very different to the one Coolair joined back in 1980, but we have always tried to innovate to ensure our continued success.”

The firm is looking to increasingly sustainable air conditioning solutions as it enters its 40th year and actively promotes the use of renewable energy technologies in their systems.

Coolair staff will celebrate the firm’s 40th anniversary at its annual conference, which takes place in the spring. Coolair will also celebrate the landmark anniversary with a charity bike ride across South East Asia in October.