When your thermostat suddenly stops working, it doesn’t just cause discomfort — it can leave your entire home’s heating and cooling system in limbo. Most people assume that thermostat failures are either due to old batteries or complete breakdowns. However, the reality is that many issues stem from lesser-known causes that are often overlooked. This presentation explores the uncommon but impactful reasons your thermostat may fail, along with simple troubleshooting steps you can perform before calling a professional.