Sometimes, you may wonder why your HVAC is not working even after all the switches are ON. It might be due to the thermostat. The thermostat batteries could be dead, or the thermostat is not set to heating mode. Sometimes, if the fan is set ON instead of AUTO, and the fan constantly runs, this ultimately stops the furnace operation.
After learning about these issues, you may recalibrate the thermostat, change its batteries, and hire our HVAC contractor in Paradise, CA, for a thermostat repair. You probably need to replace the thermostat instead of repairing it if it is broken. A broken thermostat can be the culprit of multiple heating and cooling issues.