In this video, he is staying at a house that has not returned home. The couple is away for holiday. The first step is to look at the thermostat. If your thermostat isn’t operating properly, it would suggest that all else is okay. Then, he checks to see if the insulation is sufficient. He will then visit the electrical panel and check if it is functional. The electrician will have to replace the panel if it’s no longer working before checking that unit. The unit isn’t working in this instance. The issue is in his own hands. The panel and the thermostat worked perfectly at this point. There are times when it’s hard to determine reasons why the system isn’t working. If your fan doesn’t seem to be running, it is either bad or has a bad running pad. It’s best to take it apart and evaluated. HVAC repairs are complex. A professional may be your best option. If you’re looking for more information continue watching the video. wgj16yorm7.