Video: Electric Furnace vs. Gas Furnace: Working Principle, Pros ＆ Cons, Factors to Consider
Figure 1: Heating equipment in a basement.
As winter approaches and the need for a reliable heating system becomes paramount, the choice between an electric
furnace and a gas furnace is a decision many homeowners must grapple with. Both options have their merits and
drawbacks, and understanding the differences between them is crucial for making an informed decision that suits your
heating needs and preferences.
In this comprehensive guide, we will explore the key distinctions between electric and gas furnaces, considering
factors such as efficiency, cost, environmental impact, and overall performance. Let’s first learn some basic
knowledge about electric and gas furnaces.
1. Working Principle of Electric Furnace
Electric furnaces operate on a straightforward principle. They use electricity to generate heat through a process known as resistive heating. When the thermostat signals the need for heat, electric currents pass through heating elements, typically made of metal coils. As these coils resist the flow of electricity, they generate intense heat. The blower fan then distributes this heat through the ductwork to warm the entire home.
Figure 2: Components of an electric furnace from www.ahrinet.org.
2. Pros and Cons of Electric Furnace
Pros of Electric Furnace
●Simplicity: Electric furnaces have fewer components, making them relatively easy to install and maintain.
●No Combustion Byproducts: Since there's no combustion involved, electric furnaces produce clean and safe heat, free
from harmful byproducts like carbon monoxide.
●Longevity: Electric furnaces generally have a longer lifespan compared to gas furnaces due to the simplicity of
their design.
Cons of Electric Furnace
●Higher Operating Costs: Electricity tends to be more expensive than natural gas in many regions, leading to higher
monthly heating bills.
●Dependence on Electricity: Electric furnaces rely entirely on electricity, making them vulnerable to power outages.
3. Working Principle of Gas Furnace
Gas furnaces operate by burning natural gas to produce heat. When the thermostat triggers the furnace, a valve opens to release natural gas into the burners. The burners ignite the gas, creating a flame. This flame heats a metal heat exchanger, and the blower fan then circulates air over the exchanger, warming it before distributing it throughout the home. The combustion byproducts, including carbon monoxide, are safely vented outside through a flue.
Figure 3: Gas furnace working diagram from hvacrschool.com.
4. Pros and Cons of Gas Furnace
Pros of Gas Furnace
●Lower Operating Costs: Natural gas is often more cost-effective than electricity, leading to lower monthly heating
expenses.
●Quick and Efficient Heating: Gas furnaces can heat a home quickly and are known for their high warmth output.
●Reliability in Cold Climates: Gas furnaces perform well in extremely cold conditions, ensuring consistent heating
even in harsh winters.
Cons of Gas Furnace
●Complex Installation: Gas furnaces require a gas line and ventilation system, making the installation process more
complex and potentially more expensive.
●Combustion Byproducts: The combustion process produces byproducts, necessitating proper ventilation to avoid safety
hazards.
●Shorter Lifespan: The combustion process and the presence of more components may result in a shorter overall
lifespan compared to electric furnaces.
5. Electric Furnace vs Gas Furnace: 6 Factors To Consider
5.1 Efficiency: The Battle of Energy Consumption
One of the primary considerations when choosing between an electric and a gas furnace is efficiency. Efficiency not
only impacts your monthly utility bills but also contributes to the overall environmental footprint of your home
heating system.
Electric Furnace Efficiency:
Electric furnaces are known for their simplicity and high efficiency. They convert nearly 100% of the electricity
they consume into heat. However, the cost of electricity tends to be higher than that of natural gas in many
regions, which can offset the efficiency gains.
Gas Furnace Efficiency:
Gas furnaces, on the other hand, are highly efficient in terms of cost. Natural gas is often more affordable than
electricity, making gas furnaces a cost-effective option for heating. Modern gas furnaces also come with high Annual
Fuel Utilization Efficiency (AFUE) ratings, indicating their efficiency in converting gas into heat.
Consideration:
When comparing efficiency, it's essential to weigh the cost of energy in your region. In areas where electricity is
more affordable, an electric furnace might be a competitive option. In regions with lower gas prices, a gas furnace
might offer better overall efficiency.
Figure 4: Close-up of flames on a natural gas in a furnace.
5.2 Installation Costs: Breaking Down the Initial Investment
The upfront cost of installing a heating system is a significant factor for homeowners. Understanding the
differences in installation costs between electric and gas furnaces can help you plan your budget effectively.
Electric Furnace Installation:
Electric furnaces are generally less expensive to install than gas furnaces. They don't require gas lines,
simplifying the installation process. This simplicity can result in lower labor costs and a quicker installation
timeline.
Gas Furnace Installation:
Gas furnaces, on the other hand, involve more complex installations. They require venting systems to expel
combustion byproducts, and a gas line must be run to the furnace. The installation of a gas furnace typically
requires a professional with expertise in handling gas lines and ventilation systems.
Consideration:
While electric furnaces have a lower initial investment, it's important to consider long-term operating costs. Gas
furnaces may have higher installation costs, but their lower ongoing operational expenses can make them more
cost-effective over the life of the system.
Figure 5: Gas furnace installation.
5.3 Operating Costs: The Long-Term Financial Picture
Beyond the initial investment, the day-to-day operating costs of an electric or gas furnace play a significant role
in the overall financial impact on homeowners.
Electric Furnace Operating Costs:
Electricity rates can vary widely, and in some regions, they are notably higher than natural gas rates. This can
result in higher monthly heating bills for homes with electric furnaces. However, the high efficiency of electric
furnaces may offset some of these costs.
Gas Furnace Operating Costs:
Natural gas is often more affordable than electricity, making gas furnaces economical to operate. Modern gas
furnaces with high AFUE ratings ensure that a significant portion of the energy in the gas is converted into usable
heat.
Consideration:
When assessing operating costs, it's crucial to factor in both the cost of the energy source and the efficiency of
the furnace. A more efficient furnace may consume less energy, mitigating the impact of higher electricity rates.
Figure 6:Gas furnace flame ignitor.
5.4 Environmental Impact: Navigating the Green Path
As environmental consciousness becomes increasingly important, the environmental impact of heating systems is a
crucial consideration for many homeowners.
Electric Furnace Environmental Impact:
Electric furnaces produce zero on-site emissions since they don't burn fuel. However, the environmental impact
depends on the source of the electricity. If the electricity is generated from renewable sources, such as wind or
solar, the environmental footprint can be significantly reduced.
Gas Furnace Environmental Impact:
Gas furnaces burn natural gas, releasing combustion byproducts such as carbon dioxide and nitrogen oxides. While
modern gas furnaces are designed to be more environmentally friendly than older models, they still contribute to
on-site emissions.
Consideration:
To minimize the environmental impact, homeowners can opt for renewable energy sources when using electric furnaces
or choose high-efficiency gas furnaces with advanced combustion technologies.
5.5 Heating Performance: The Warmth Factor
Ultimately, the primary function of any heating system is to provide comfort by effectively warming the living
spaces. When comparing electric and gas furnaces in terms of heating performance, several factors come into play.
Electric Furnace Heating Performance:
Electric furnaces deliver a consistent and even heat. They are known for their precision in maintaining the set
temperature. However, they might struggle in extremely cold climates, as they may require more time to generate
sufficient heat.
Gas Furnace Heating Performance:
Gas furnaces are well-suited for colder climates, as they can produce higher temperatures more rapidly. They provide
a steady and reliable heat, ensuring that homes reach the desired temperature quickly.
Consideration:
Consider your local climate and the heating demands of your home when evaluating the heating performance of electric
and gas furnaces. If you live in an area with harsh winters, a gas furnace might be a more suitable choice.
5.6 Maintenance and Service Life
Electric Furnace:
Electric furnaces are known for their longevity and low maintenance requirements. With fewer moving parts and no
combustion process, the risk of wear and tear is minimized. Regular checks on the heating elements and the blower
system are typically sufficient to ensure optimal performance.
Gas Furnace:
Gas furnaces may require more frequent maintenance due to the combustion process and the presence of more
components. Regular inspections of the burner, heat exchanger, and flue system are crucial to ensure safety and
efficiency. Despite maintenance needs, gas furnaces can still provide a reliable service life, though it may be
slightly shorter than that of electric furnaces.
Figure 7: Dirty furnace filter replacement.
6. Conclusion: Making the Right Choice for Your Home
In the electric furnace vs. gas furnace debate, there is no one-size-fits-all answer. The choice between these two
heating options depends on various factors, including your geographical location, budget, environmental priorities,
and heating preferences.
Assessing the long-term costs, environmental impact, and heating performance will guide you towards a decision that
aligns with your unique needs. Whether you opt for the simplicity of an electric furnace or the cost-effective
warmth of a gas furnace, investing time in understanding these heating systems will ensure your home stays
comfortably warm through the coldest winter days.
