Wondering if your heater is saving you money or wasting energy? An energy-efficient heating system not only keeps your home cozy but also reduces utility bills and your environmental impact. From low energy bills and even heating to advanced features like smart thermostats and high AFUE ratings, there are clear signs that your system is performing at its best. Check out these 10 key indicators to ensure your heater is running efficiently and helping you stay warm without breaking the bank.