The Leader chatted to Lysaght's Refrigeration and Air Conditioning owner Jo Lysaght, who said she has had to turn many potential customers away because they were so busy.

"We've been booked out till the Christmas closure since about the beginning of November," Ms Lysaght said.

"September and October we could attend to 95 per cent of the calls we took in but we've now been turning away 95 per cent of the calls due to overbooking.

"All my guys are busy right now and they're doing work that was booked in four to six weeks ago."

She said the company was booked out until the third week of January with people needing their systems fixed or wanting new systems installed.

It's a similar story at Laser Electrical Tamworth.

Business development manager Kel Clarke says many locals are wanting new reverse cycle ducting systems and high-wall split systems installed but they're having to wait a little while.

"We may not have been able to schedule the day they've called but we've scheduled in the next available appointment," she said.

Ms Lysaght said locals need to think ahead for the summer months so they can get booked in quicker.

"What's also happening is maintenance becomes critical, they're overheating, they're performing poorly," she told the Leader.

"Anything you want in summer you should get it checked in September. Things that are broken down or parts needed can be prepared for summer.

"But to leave it till November ... we really struggle every year to help people with their problems."

Residents without air-conditioning aren't the only ones struggling in the heat. The tradies doing the work have had barely any time to cool off, the business owner said.

"The boys are working out in long hours in the heat. They're fantastic staff doing their absolute best," Ms Lysaght said.