How would we get ready for summer? We recommend you change your filters first. In Arizona we recommend you change your filters every 30 to 90 days or so. Second, schedule a maintenance call for a technician to come out and get your unit cleaned and ready for the heat. Your unit needs to be cleaned for it to run at peak performance, and if things are looked at before the heat comes you have a lower chance of it breaking downing the middle of summer.