Do you feel like looking at the internal components of your furnace is like looking at a car engine? Thankfully, the furnace is not that complicated of an appliance. It will help to know what some of the key components are within the furnace so that you know what they are called and what they do.
The heat exchanger is a part that can look tubular or be made out of multiple flat-looking cells. This part is going to get very hot if the furnace was just running, so be careful when touching it. The heat exchanger separates the dangerous gasses from the clean air that you breathe, and a damaged heat exchanger can be a big problem in your home since it will essentially be allowing the dangerous gasses to be breathed in. A damaged heat exchanger can often require replacing the entire furnace to ensure that your home is safe.
One of the main components that works with the heat exchanger is the draft motor. The purpose of the part is to move the combustion gasses into the heat exchanger to heat it up. Then it pushes those gasses out through a ventilation pipe and safely leaves your home. A broken draft motor can cause the heat exchanger to not get hot.
High Limit Switch
The high limit switch has the job of ensuring the furnace isn't overheating. This can happen if you have a dirty air filter that is lacking airflow, which can cause the heat within the heat exchanger to get incredibly hot. The high limit switch will turn off the burners when it senses that this is happening, and then will keep the fans moving to cool down the furnace so that it doesn't overheat.
Pressure switches are made out of plastic or metal material, and they are typically round in shape. This part has the main job of ensuring that the combustion gasses are leaving the furnace and through the exhaust pipe. If the draft motor were to fail, the pressure switch would sense that gas is not leaving the furnace and shut it down. This prevents those dangerous gasses from getting into your home for your own safety.
These are just a few of the key components that your furnace uses. If you have a suspicion that one of these parts is damaged, reach out to an HVAC technician for help with your heating system.