What Size Furnace Do I Need??

Here's how we determine what size furnace will be best for a particular home! At Advantage, We Got You. Here's the original blog: https://www.advantageheatingllc.com/l... Timestamps: 00:00 - How Are Furnaces Classified? 00:48 - Home Size Determines Furnace Size 01:06 - What Else Affects Your Furnace’s Effectiveness? 02:31 - What Happens When a Furnace is the Wrong Size? 03:06 - How to Find the Right Sized Furnace Visit our website: https://www.advantageheatingllc.com/ Facebook:   / advantageheatingllc   Instagram: https://www.instagram.com/advantagehe... Tiktok: @advantageheating How Are Furnace’s Classified? First, you need to know how furnaces are sized to know what size of furnace you need. Furnaces don’t come in the traditional small, medium, and large. BTUs A BTU is a British Thermal Unit. Furnaces are rated in by their output in BTUs. A 60,000 BTU furnace will put out more heat than a 40,000 BTU furnace. Furnaces also have a rating based on their Average Fuel Utilization Efficiency (AFUE), or efficiency. Their efficiency rating should be on a prominent label by the Department of Energy. Efficiency is graded as a percentage out of 100. Furnaces that use less energy to produce heat have a score closer to 100%. Most modern furnaces start at 80% and go to around 97%. Home Size Determines Furnace Size The size of your home is the biggest determining factor in what size of furnace you need. Your furnace has to be big enough to provide heat to all of your home. That’s why the square footage of your home is the number you need to know to get the baseline for the size of furnace you need. It’s recommended that a furnace has 30 to 60 BTUs per square foot. The actual number depends on the climate which will get into in the next section. There are a lot of other factors that need to be considered when shopping for a furnace. Each one will affect how many BTUs you need. Insulation Another factor to consider is insulation. A furnace pumps heat into your home. Insulation keeps that heat trapped in there. Naturally, the two work together. Things to think about: How old is your home? What was the standard for insulation when your home was built? Are there rooms in your home that are not insulated? Have you had any events that could damage your insulation (such as water damage)? Bring these subjects up with an HVAC professional. They will tell you how much that will affect the heating in your home and also give them a better idea of how to meet your needs. Efficiency Another item that needs to be considered is the efficiency of your furnace. While this may not have a direct impact on the heating it provides, it will impact how much energy it uses. A furnace with a higher efficiency rating will heat your home using less energy. You will probably want to keep a furnace’s efficiency rating in mind if your home requires a substantial amount of heating. An efficient furnace that is installed properly can save you a lot of money on your energy bill. Too Small If your furnace is too small, it will struggle to heat your home. These are some issues you might encounter. It runs for very long cycles. The heating throughout your home is uneven. The energy bill is larger than it needs to be. Furnace breaks down more often or parts don’t last their full lifetime. Too Big If your furnace is too big, it will run inefficiently and will short cycle (run in quick, short bursts). This can cause a whole slew of problems. Below are some symptoms and what that will look like. It will make your home hotter than desired in some rooms. The furnace only turns on for a very short amount of time. The furnace will have a noticeably shorter lifespan. The furnace will use more energy because of the constant switching off and on. How to Find the Size of Furnace You Need We just told you all the things you need to consider finding the correct size for a new furnace. Now let's put that all together and tell you how to find the size of furnace you need. Load Calculation To calculate the number of BTUs your home requires, you will need to have a Manual J or Block Load Calculation performed. These are ways of putting all those variables into a formula to get a definitive answer on the size of furnace you need. An HVAC sales professional will perform this calculation with you. If you’re not shopping yet and are trying to figure out if your furnace is over or undersized, you can contact your local utility company and see if they provide Manual J calculations. There are also several formulas and apps available online if you wanted to try the calculation yourself. While we can’t guarantee those will be accurate, it can be a good starting place.