Recently I was discussing the best ways to keep your home cool in these sweltering months with a friend.

The question came up: Should you leave your ceiling fans running when you aren’t home or even in the room?

That got me wondering, so I decided to call some local air conditioning experts to see what they had to say.

“Waste of energy,” was the verdict from La Verne and Son Air Conditioning.

Over at Mike’s Air Conditioning I got the same ruling — and an earful about the laws of thermodynamics.

Turns out the only time you really should have the ceiling fan running is when you are in the room. Fans don’t actually cool they air, they just move it around, which helps cool you down thanks to evaporation.

Bruce Meister, service manager at Hillcrest Air Condition, says you’re much better off cleaning out your filters, having your ductwork checked for leaks or upgrading an older unit with something more efficient.

“That’s where the real money is saved,” he said.

One other tip: Make sure your ceiling fan is blowing the air in the right direction. In the summer you want it blowing down on you. In the winter you want it blowing upwards.