Yes, it is necessary to have your dryer vents cleaned on a regular basis. The National Fire Protection Association (NFPA) recommends that dryer vents be cleaned every 1-2 years. This is because lint accumulation in the vents can lead to a number of problems, including: -A fire hazard due to the build-up of flammable lint in the vent -Reduced efficiency of the dryer, causing it to take longer to dry clothes -The formation of mold and mildew in the vent due to moisture accumulation -The transfer of heat from the dryer into the home, which can increase your energy bills

It is not necessary to have the dryer vents cleaned if they are not visibly dirty. However, it is important to clean the lint filter after every load of laundry in order to ensure proper air flow and to prevent the build-up of lint, which can cause a fire.