NASHVILLE, Tenn. (WTVF) — This is a busy time for HVAC technicians servicing AC units, which are working overtime to keep Nashville residents cool during this heat advisory.

It's usually during this time when technicians also see a lot of repairs.

"It's about six degrees over what we set it at, and we don't keep it set low. Like it's like a 72 so it's 78 and then upstairs and in the bonus room, it's 80." said Jay Hutchens.

Hutchens says he went to crank up his air conditioning units in his South Nashville home and it wasn't working properly.

"With the weather getting warmer over the last couple of weeks, we've had a hard time with our AC keeping up with the heat," Hutchins said. "And so, we called Hiller to come out and take a look at it. And so, they're telling us that we won't be able to just replace the refrigerant, but probably will have you looking at some, maybe even some new units too."

Others in Hutchens' neighborhood are in the same boat. NewsChannel 5 saw two other cooling companies in the same neighborhood.

Technicians say it's common this time of year.

"There have been times whenever I was driven by street and there were four or five different companies at each different house that I was going to," said Jason Huber with Hiller Plumbing, Heating, Cooling and Electrical.

Huber says when temperatures reach the degrees, we're facing this week the calls for repairs come rolling in.

"Lot to do with summer because a lot of people they just run their AC and they think that they turn the thermostat down a couple of degrees it might keep up but that's never the case," he said.

He says broken systems are typically caused by two major factors, which are old age and refrigerant.

So, he is asking homeowners to get their HVAC units checked on regularly.

"Maintenance is key. It's just like a vehicle. Do you change your oil? Do you rotate your tires? Change your wiper blades? It’s maintenance key," Huber said.

It's a message homeowners like Hutchens is echoing.

"Well, this is usually about the time when you realize you need a new air conditioning. So just like you know, you need a new heater in the middle of winter. So, it's not unexpected. But you know that kind of news you always wish you could put it off a little longer."

Hiller recommends getting maintenance checks on your HVAC units in March and April.