Common air conditioner problems: a guide
Your air conditioning unit needs regular cleaning - otherwise it will begin to smell mouldy, and lose performance.
This isn't only unpleasant, it's unhealthy. As it circulates warm, smelly air, a dirty ac unit will increase your chances of infections, allergies, and asthmatic problems.
Dirt and mould also make your air conditioner less efficient - so it won't cool your home or office very well.