White smoke from under the hood while engine is still cold

Sorry if this question isn't in the right section. I'm not very good with cars so I'm not really sure what category my problem falls under.
So here is the situation. There is white smoke coming out from the back of the engine after driving my car for about 5 minute. I've attached a picture with an arrow pointing to the general area of where the smoke comes out from. I noticed when this occurred, the engine will still be cold and the thermometer doesn't indicate that my engine is overheating. I noticed if I turn my heater and a/c off, everything will be fine (no smoke). However, when I turn my heater on, I'll see smoke coming out from underneath the hood. When I switch to my a/c, the smoke will be blown into the inside of my car through the a/c vent. One more thing I would like to mention is a couple of weeks before all of this happened, there was actually a smell of something burning when I turned on the heater. The a/c didn't produced any burning smell though. Any help will be greatly appreciated! Thanks in advance.