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Maximize system performance by replacing your filter at the start of summer and the start of winter.
Dust in the home? Pet dander? Ask your Westinghouse expert about a high-efficiency air filter or electronic air cleaner. They work at least seven times better than a standard filter at removing dust and other particles, and may need to be replaced just once a year.
If you have a standard furnace filter, you should check it monthly to make sure it's not blocking airflow. At a minimum, your filter should be changed twice a year.