About 60% of all U.S. households rely on furnaces for heating. This is an exciting time to upgrade because of many innovations and features. Still, it’s a significant investment and decision. Let’s explore what to look for in your ideal furnace.
Heating Output
Sizing a furnace refers to estimating your home’s optimal heating output. Accurate sizing is imperative. If a heating system is too big or small, it’ll be less efficient and more prone to wear. In the U.S., the industry measures heating output in British thermal units (BTUs). The general guideline is that you need 30 BTUs per square foot. This number is adjusted based on your home’s layout. Multistory homes, rooms with tall ceilings and long, skinny homes with multiple wings all require more effort to heat than a perfectly square, one-story home. Your installer will conduct a more accurate estimate through a load calculation, such as the ACCA Manual J approach. You may also see furnaces rated by tonnage. One ton is equal to 12,000 BTUs.
Power and Fuel Options
Electric furnaces are heating systems that generate heat with electric coils. These systems are highly efficient but not necessarily cost-effective due to the price of electricity. If your only option is electric, perhaps consider hybrid heating that combines a heat pump and furnace.
Most U.S. homes with a furnace have a fuel-fired model. Even fuel-burning furnaces need electricity, such as for lighting and displays. Many have electric ignition systems rather than pilot lights, which manufacturers are phasing out. Natural gas is the most popular option because it’s the cheapest and most convenient. The alternatives for homes that don’t have natural gas access are fuel oil and liquid propane.
Annual Fuel Utilization Efficiency
The industry measures the energy efficiency of furnaces using annual fuel utilization efficiency (AFUE). AFUE is a ratio of the energy consumed to the heat successfully delivered. The higher the value, the more efficient the furnace.
Electric furnaces have AFUE ratings close to or at 100. That doesn’t tell the whole story, though, due to the cost of electricity relative to the cost of fuel. When comparing electric fuse so using estimated watts. You’ll find this information on the yellow EnergyGuide label.
The standard modern gas furnace has an 80 AFUE rating. That means it converts 80% of the fuel it burns into heat that reaches the living spaces. Standard or mid-efficiency furnaces can range up to AFUE 89.
ENERGY STAR
The U.S. Department of Energy (DOE) sets a minimum AFUE as a legal requirement for HVAC manufacturers. The Environmental Protection Agency (EPA) sets even higher standards. They aren’t legal requirements, but they let manufacturers earn ENERGY STAR certification on their products. The ENERGY STAR label gives consumers confidence they’re choosing an efficient system. The label is also a requirement for many energy incentives. To find the rebates available in your area, you can search by zip code on the ENERGY STAR website.
High-Efficiency Furnaces
The EPA generally reserves ENERGY STAR certification among furnaces for high-efficiency fuel-burning models in particular. These models must have a 90 AFUE rating and can range up into the high 90s. Let’s explore the innovations that make this high efficiency possible.
Multi-Stage Blower
A traditional furnace is a single-stage system, which means it runs at the same speed all the time. Multi-stage furnaces typically have a low and high stage. These models can conserve fuel by using the low stage to achieve minor temperature adjustments. Then, they can run at high speed like a single-stage furnace when fuller heating is necessary.
Variable-Speed Blower
An even more sophisticated approach is a modulating furnace. These systems have a variable-speed blower that can ramp up and down, typically in 5% increments. That lets a furnace conserve even more energy by running only at the precise speed required.
Condensing System
The furnaces the EPA awards ENERGY STAR certification to are often condensing. This includes single-stage, multi-stage, and modulating condensing furnaces. Traditional fuel-burning furnaces lose heat through the venting of toxic gases. Condensing furnaces limit this heat loss. They have a second heat exchanger that reclaims heat from the gases through condensation before venting them outside the home.
Programmable or Smart Thermostat
Purchasing a new furnace is also an excellent time to upgrade your thermostat. Programmable thermostats are precise digital thermostats that support automatic temperature scheduling. The DOE estimates that you can lower annual heating costs by up to 8% that way. Smart thermostats build on that feature set with Wi-Fi for remote access and control. They often have other advanced features, such as learning and energy monitoring.
Zone Control
Traditional forced-air furnaces are single-zone systems. In other words, they deliver heating evenly throughout the entire home. Zone control allows the furnace to distribute heating to each zone differently based on its unique needs. The DOE estimates that this approach can lower annual heating costs by up to 30%. You can, for instance, keep the bedrooms toasty at night while maintaining a more economical temperature throughout the rest of the home. Zone control requires some additional equipment. That includes a smart thermostat with zone control, a variable-speed blower, and duct dampers or smart vents.
Filtration
All furnaces require filtration. In many cases, the filter is at the supply vent for the ducts. In other cases, you install the filter directly into the furnace unit. While the core goal of such filters is to keep the furnace clean, they can help improve indoor air quality. The industry rates HVAC filters using the minimum efficiency reporting value (MERV). The higher the MERV rating, the better the filtration. If a furnace has a MERV-8 filter, it will trap 70% of particles 3.0 microns in size and larger. A MERV-13 filter, on the other hand, will trap 90% of those particles.
Humidification
Low relative humidity (RH) can be a byproduct of running a furnace. Furnaces heat air quickly and to a high temperature. That heated air can then absorb considerable moisture from the environment, including you. Some furnaces have an integrated bypass humidifier to help offset this effect. You can add a bypass humidifier to most furnaces. For all ducted systems, you can also add a whole-house humidifier that doesn’t rely on airflow from the system.
Manufacturer Warranty and Extended Warranty
Warranties can vary greatly between brands and even from one manufacturer’s model to the next. Read the fine print before purchasing. Determine what your requirements are as the consumer and what the contract covers. Many manufacturers also sell extended and more robust coverage. That can be worth it depending on the cost and what’s added.
Maintenance Requirements
Warranties often require professional maintenance once a year. Note any special requirements that the coverage may have. Pay attention to the manufacturer’s overall maintenance suggestions as well. Maintenance for condensing furnaces, for instance, is often more involved.
Trusted Furnace Installation in Bradley and Peotone
Kulacz & Sons Heating & Cooling, Inc. is a family-owned and -operated HVAC company since 1979. We have locations in Bradley and Peotone, IL and serve the surrounding areas. Our NATE-certified technicians install, maintain, and repair all furnace brands and models. We specialize in many other heating, cooling, ductwork, and indoor air quality technologies as well. Call today or contact us online with questions and to schedule a free in-home furnace installation consultation.
