Came out to customers home for a no heat call. Customer stated that they just moved in recently and the heater wasn’t working properly. The home had a nest thermostat installed before they moved in and she was able to operate it, but only the fan would come on. I checked system over and found only the blower running when calling for heat. I checked the thermostat and went through equipment settings. The thermostat was set up for electric heat instead of gas, which was the cause of the blower running with no heat. I reprogrammed the settings to match the unit, and cycled the heat on. System started up with no issues, and system cycled off properly. Discussed with customer about maintenance upkeep and filters.