Get data on recognizing caution symptoms along with peculiar noises or smells coming from an air conditioner; early detection

https://zenwriting.net/abregeivva/avoiding-common-pitfalls-during-diy-hvac-projects-t1x4

Get methods on spotting caution signals corresponding to unusual noises or smells coming from an air conditioner; early detection ends in well timed interventions stopping added spoil down the road!