Well its that time of year were you turn on the a/c and hope it works still. The AC in the still works but when I turn off the compressor and leave the blower on I start to smell a musty wet smell coming from the vents. Could i have a blocked condensation tube?

 

Run the a/c for a while and if you have water dripping out on the ground, your tube isn't blocked. Not much dirt, ect gets in there through the cabin filter.

Air will pass through your evaporator (the core inside your HVAC system) Condensation will form on the evaporator and most is supposed to drain out (as you see a small puddle of water when the a/c is running.) Not all of it does drain out and you can get great things like mold, ect growing in your system.

There are sprays you can buy (or lysol) to spray into the intake on the hood cowl while running a/c and heat. The most effective is a mister that some shops have the kill bacteria and smells. The machine is usually around 4-500$ to buy from MAC or Snap on. But chances are you will want to pay 50$ or so for a shop to do it.

 

What I did was take some fabreze and spray it into the ducts from the outside
This helped a lil

 

rinse and repeat