How often should I replace the filter?

The frequency of filter changes is driven by how much your heating and air conditioning system operates, which is also driven by conditions within your home. Start by checking your system’s filter(s) at least once per month. Hold the used filter up to the light and compare it to a clean ‘spare’. When light is obscured by captured dirt and dust particles, the old filter should be changed. As a rule of thumb, if you have a standard-type air filter, you should clean or change your filter every two months.