I work in an HVAC company (heating, ventilation, and air conditioning, for those unfamiliar). One of my main duties is warranties. Since it’s summer, most people are running their A/C a lot more and so we’re getting more service calls. A good 50% of the issues we have are caused by dirty filters. If the filter is dirty, it can cause major problems with your system over time. I honestly thought this was common knowledge, but we have people who’ve been under our warranty for nearly two years who haven’t changed the filter ONCE. Change it once every 3 months. If you have a lot of pets, leave your doors or windows open often, or have been running your A/C a lot, check it once a month and replace as needed. They’re super cheap, much cheaper than the replacement of a condenser would be.