Is a Gas Furnace or Gas Fireplace More Efficient?
When it gets cold, many people wonder if it is more fuel efficient to turn on their gas furnace or huddle around a gas fireplace. Unfortunately there is no simple answer to this question, but there are a few things to understand when you’re wondering which way to get warm.
Gas appliances have a BTU consumption rating that indicates the amount of gas they use in an hour. The rating can be found in the appliance manual or on the appliance label and it will usually have two numbers, one that indicates the BTU consumption when the appliance is on its highest setting and one for when it is on its lowest setting.
You might think that whichever has the lower consumption rating is automatically your best bet, but there is more to consider.
Another factor is the efficiency of the heater. This measures how much of the fuel used actually gets turned into the heat you feel. Extraction efficiency is also listed by the manufacturer on a label or manual for gas furnaces. A higher extraction rating is a good sign but even that doesn’t tell the whole story.
Some of the heat gets lost in the ductwork as it travels throughout the house. The actual amount of heat that gets to you can’t be measured by a manufacturer for a gas furnace system because it is different for every house depending on factors like amount of ductwork and the house’s insulation.
However, for a gas fireplace the actual amount of heat can be measured because it delivers heat directly into your home.
This difference means that the efficiency listed on a gas fireplace can’t always be compared to the efficiency listed on a gas furnace in a meaningful way.
Choosing to turn on a gas fireplace or a gas furnace really depends on what you want to accomplish. Usually it is more fuel efficient to have the fireplace on because it doesn’t lose any heat traveling through ductwork, but that also means the heat is localized and won’t warm the entirety of a large house. So if everyone is cozied up in one room it is often better to have the fireplace on. If warming an entire house is what you are after it is usually better to turn on the furnace.
You should always make sure your appliances are energy efficient models and are running properly to avoid wasting fuel.