If it is time to replace your furnace, you will want to buy the most energy-efficient option possible. However, there are at least two major considerations before you make a final decision.
Signs You Have an Ineffective Furnace
If you are not sure of the efficiency of your furnace, there are several signs of poor efficiency that you should note, including:
- Uses a pilot light or non-electronic ignition
- Offers unsealed combustion that allows more heated air into the environment
- Feels a surge of hot air every time that the unit turns on
- Lacks a method of removing combustion gases from the system
- Requires manually lighting a pilot light
- Needs floor bracing or other methods of reinforcement to handle the unit’s weight
AFUE Number Meaning
Make sure that you examine the Annual Fuel Utilization Efficiency (AFUE) number of the unit that you are considering. This number tells you how much of every $1 provides heat for your building.
Every unit sold in the United States must have at least a 78 AFUE rating. If your unit has a 78 rating, then for every $1 you spend on heat, you are getting $0.78 in heat. The average home heating bill is about $1,800 annually. Therefore, you are wasting $596 that is not heating your home.
Now, assume that you buy a unit that has a 98% AFUE rating. That means that $0.98 is going to heat your building. Therefore, if you have the average home with a $1,800 heating bill, you only pay $36 annually for heat not used in your building.
Factors Making a Difference in Heater Efficiency
Many different factors affect a new furnace’s efficiency, including:
- Heat Exchangers – Manufacturers use various materials and methods to make their heat exchangers. The government requires manufacturers to print the efficiency of the heat exchangers. Generally, units that have more surface area will have higher ratings. Condensing gases in a second heat exchanger improve efficiency.
- Burner Settings – Usually, a furnace with more burner settings will be more efficient than units that only have one. Some units use the same amount of power regardless of the number of degrees it needs to raise the air temperature. While many older furnaces have only one power level, newer furnaces have two or more power settings. These systems are more efficient than one power units. The most efficient units have modulating heat. These units offer precise heat control so you are not paying for your rooms to be too warm. Many can keep areas within two degrees of the temperature setting. Generally, 80% AFUE furnaces with two-step or modulating heat are more efficient than 95% AFUE furnaces with one-step heating.
- Fuel Source – The United States Department of Energy says that natural gas is the most energy-efficient way to heat your home in terms of dollars spent per BTUs generated. Experts rate electric furnaces as 100% efficient. Still, that number is deceiving because up to 30% of electricity is lost because of the energy required to produce electricity and the amount of loss in your electric lines. Fuel oil furnaces are not as efficient unless you consider the newer ones that run on a combination of fuel oil and biodiesel. Finally, propane is less efficient than natural gas and fuel oil, but it requires a storage tank.
- Furnace Ventilation – The efficiency of your furnace also depends on its ventilation. Natural flue pipes are the most common, and they work by forcing hot air up and through vent pipes on your roof. This system usually lowers the energy efficiency of your furnace. A second option is direct ventilation. In this system, the gases produced while heating your home go to a second heat exchange which cools them and forces them out of the system in liquid form.
- Furnace Ignition Systems – Up until the late 1990s, almost all gas furnaces had a pilot light. That is not true today as many have electronic ignition systems, and these options increase the energy efficiency of your furnace.
If you are looking for a more efficient type of furnace ignition system, consider these options available today:
- Direct Spark Ignition – These furnaces have no pilot light, but they supply gas to a burner every time you need heat.
- Intermittent Pilot Ignition – These furnaces have a pilot light that only works when the unit is providing heat
- Hot Sensor Ignition – Most use a silicon-carbon element to send a specific amount of electric voltage to the ignitor, triggering the main valve to open.
- Mercury Bulb – The bulb sparks ignition, which opens the main gas valve.
Your Results May Be Different
While comparing AFUE numbers is a great place to begin, your operating costs of a high-efficiency furnace may be different. Many other factors come into play.
If your home has air leaks, then you may be losing heat through them. An easy way to find out where drafts occur is to light a candle and to turn off the furnace and any ceiling fans. Then, walk through your home. When the candle flickers, you need to identify the source of the draft. Windows and doors can be significant areas of concern. Before you buy a furnace, get a professional to do a load calculation test that will show you exactly how airtight your home is currently.
You need a well-insulated home. Most homes in the northern United States should have R-49 insulation that is 16 to 18 inches thick. At the same time, you need to ensure that your home has adequate ventilation. Installing an energy and heat recovery ventilator can help solve this problem, and these extras often come with an energy-efficient furnace.
How to Choose the Right Energy-Efficient Furnace for Your Home
When you are looking for a new energy-efficient heater, the first consideration is to choose the right size of furnace. Generally, you will need to multiply the square footage by 20 BTUs per square foot, but you will need more if you have high ceilings or large windows.
Choose a furnace with a high AFUE rating. You will enjoy the savings while you own the home. If you decide to sell your house in the future, it can be a great selling point.
Pick the features that you want the most because you will be happier with your unit. A whole-house ventilator and humidifier can be a great add-on that will keep you and your loved ones more comfortable.
Select top-quality filters. Be sure to select one that fits your new furnace. Generally, you will need to replace it every three months.
Work With a Professional
Working out all the details can be an overwhelming experience. Therefore, you should contact Holbrook Heating & Air Conditioning before you make a final decision. Our team of professionals will guide you through each step of the process. You will love the way that we show up on time and clean up after ourselves.
If you are not looking for furnace installation, we can also provide air conditioning installation, repair, and maintenance services, as well as work with water heaters. If you live in upstate New York, give Holbrook Heating & Air Conditioning a call today!