Sounds from engine when I turn on heat or air..

Whenever I turn on my air-conditioner or my heat a sound come from the engine and it sounds like this.. chic a tee chic a tee chic a tee whenever, I stop the heat or air it stops..

Any suggestions..

The chic a tee chic a tee sound you hear under the hood may be your Air Conditioner Compresser engaging, Simple things first: Have you checked your Antifreeze in you radiator yet?