Carrier Gas Furnace Troubleshooting
When the temperature drops you want to make sure your gas furnace is functional and working to keep rooms warm. Is your Carrier gas furnace having issues? Below we have an essential Carrier gas furnace troubleshooting guide to help you solve minor issues that might be causing problems. Performing preventative maintenance can help prevent disasters and keep your machine running smoothly, so check out our Carrier furnace guide on replacing the filter.
Furnace Not Turning On
- Thermostat power - Check that the thermostat is properly getting power. If your thermostat uses batteries, the batteries might need to be replaced.
- Check the settings - Make sure your thermostat is set to “heat” and not in the “off” or “cool” position. Look at the fan switch and ensure that it is set to “on”. If you turn the fan setting to “on” and the furnace still does not start, this may require an authorized service agent to assist.
- Temperature setting - Look at the set point or the temperature setting on the thermostat. If it is low, the furnace won’t turn on until the room temperature drops below that number. Try setting it higher and then check that the furnace turns on.
- Circuit breaker - Check the circuit breaker or fuse box to make sure it wasn’t tripped and that the furnace is getting power.
- Pilot light out - If the pilot light is out then the furnace will not turn on. Use your specific model’s manual to get further steps on an unlit pilot light. If you smell gas or suspect there could be a leak, do NOT turn any switches or attempt to relight the pilot light. Immediately exit the building and call the gas company to check.
- Check gas supply - Ensure that the gas supply is still on and connected. The gas cutoff valve near the furnace should have the handle parallel to the gas line. If you smell gas or suspect there could be a leak, do NOT turn any switches or attempt to relight the pilot light. Immediately exit the building and call the gas company to check.
Furnace Turning On/Off
- Check air vents - Make sure there is nothing blocking the air vents and that they are open.
- Clean out the air filter - If the air filter is full of build-up and is dirty, it can restrict airflow and cause the heat exchanger to overheat. Try cleaning the filter to resolve the issue.
- Check thermostat settings - Look that the thermostat is set to “heat” and the fan is set to “on”. If those are both correctly set, there are a couple different reasons the furnace is turning on and off constantly. Either the system is not sized correctly for the home, the thermostat is too close to the heating source or the thermostat is faulty. These are all issues that will require an authorized service agent to assist.
Furnace Making Noise
- Whistling sound - Check that the air filter is free of build-up and not clogged. Sometimes if the filter is blocked it will make noise.
- Loud when starting - If you hear a loud ignition sound when the furnace starts, it could be a clogged burner. You will need to contact an authorized service agent to assist with this issue.
- Rattling sound - Check the ductwork and see if any has a loose connection. They can rattle with air flow if not properly connected.