It is probably widely known that high efficiency furnaces can considerably reduce your heating bills but what makes them to be such great energy savers? To answer this, we’re going to discuss several of the generally common parts of a high efficiency gas furnace.
Why is a High Efficiency Gas Furnace So Efficient?
Today, we have furnaces that perform more effectively than the ones that were fitted about a decade or two ago. This is as a result of modern features and technologies that have been developed in the past couple of years. It is also due to the simple fact that furnaces are constructed better these days.
According to High Performance HVAC Heating and Cooling these developments have helped the high efficiency furnaces to achieve two things: get increased heat from the gas they utilize and only use the needed quantity of energy for the task at any point in time.
Common Parts of a High Efficiency Gas Furnace
- Electronic ignition: Furnaces these days utilize an electronic ignition instead of the gas-run pilot lights that older furnaces use. This new ignition is used only when the furnace has to switch on. This saves more energy than leaving a small flame going constantly.
- Two-stage heating: Here in the St. Louis area, temperatures can change considerably from week to week and even day to day. This is why most high efficiency gas furnaces have two-stage heating. The lower stage utilizes less energy and is used most of the time. The higher stage comes on only when the weather is extremely cold (so more heat is needed).
- Variable speed blower: Much like two-stage heating, a variable speed blower functions at various levels depending on the needed capacity at any point in time. In situations where increased airflow is required (such as when your air filter starts getting blocked), a quicker speed is utilized. When less airflow is required, the blower changes to a slower speed to save energy.
- Second heat exchanger: A high efficiency gas furnace that has an AFUE rating of over 90% percent is a “condensing furnace.” This means it utilized a second heat exchanger to obtain heat from the exhaust gases that would have been expelled out of your home if you used a less efficient furnace. This lets condensing furnaces work better while consuming less fuel.
- Sealed combustion: For the process of combustion to work correctly, your furnace has to take in a particular quantity of air. Sealed combustion furnaces take in air from outside unlike furnaces with unsealed combustion which use (heated) air from inside your home. This sealed combustion helps to save energy and enhance safety levels.