Here’s what you need to know about both gas and electric furnaces

At ABC Cooling, Heating & Plumbing, we get a lot of great questions from our customers. Here’s a common one that homeowners want to know more about: when it comes to gas and electric furnaces, is there a difference?

The answer, simply put, is yes. Gas and electric furnaces have different installation needs, operate in very distinct ways, and often result in very different energy costs for the homeowner. In this article, we’ll break down the differences between these two types of systems and provide you with a starting point for deciding which one might be right for your home.

If you’re looking for a new heating system here in Hayward and the Bay Area, your next step is to contact our team. We offer free in-home estimates on new gas and electric furnaces, as well as other types of heating systems such as heat pumps. We can help match your home to the perfect new system.

Get to know: Gas Furnaces

How do gas furnaces heat your home?

Gas furnaces heat your home by combusting fuel—in this case, natural gas—in a sealed chamber within the furnace, and then transferring the heat energy released to air on the other side of the heat exchanger. This heated air is then blown out of the furnace and into the air ducts of your home, where it gets distributed to individual rooms. The furnace continues to burn fuel until the home is heated to the desired temperature.

As a Carrier dealer, we install both gas and electric furnaces here in Hayward and the Bay Area.

A Carrier gas furnace is an energy-efficient option for your home.

The efficiency of a gas furnace can be measured by its Annual Fuel Utilization Efficiency (AFUE) rating. Essentially, an AFUE score indicates how much heat energy the furnace is able to extract from its fuel, with the remaining going to waste. The higher the AFUE, the less natural gas the system uses to produce more heat. AFUE is a great way to compare one gas furnace against another gas furnace. However, there are limitations to using AFUE to evaluate all types of furnaces, which will be discussed in the electric furnace section below.

Evaluating gas furnace efficiency

Since the early 1990s, the U.S. federal government has mandated that all new furnaces have a minimum AFUE of 78%. This score indicates that the furnace is able to convert 78% of the gas to heat, with 22% waste. Most modern furnaces, however, do a lot better than that federally mandated floor. In fact, many top-tier gas furnaces are able to convert 95-98% of their fuel, partially due to advances in design that better capture heat energy and conserve gas.

Buying a gas furnace

If you’re interested in installing a gas furnace in your home, compare the AFUE of different models when making your decision. A gas furnace with 85% AFUE may cost less initially, but paying more for a furnace with 95% AFUE will eventually pay off through lower winter heating bills. To further balance the scales, there may be local utility rebates in your area to reimburse you for the installation of a high-efficiency gas furnace.

Get to know: Electric Furnaces

How do electric furnaces work?

Unlike gas furnaces, electric furnace operation does not involve any form of combustion or flame. Instead, they generate heat energy by running electricity through resistor coils inside of the furnace. These coils become superheated. The furnace’s internal blower then moves air through these coils, heating the air so that it can be distributed to the rooms of your home. In many ways, the hairdryer on your bathroom sink is a miniaturized, handheld electric furnace! Both systems operate using the same principles.

Evaluating electric furnace efficiency

As we hinted at above, AFUE is not a great means for evaluating electric furnace efficiency in the real world. Why? Well, all electric furnaces are somewhere between 95% and 100% AFUE, with many being able to transform all the electricity they use into heat energy. Great, you might think. Sounds like an electric furnace is a more efficient option than a gas furnace.

Well, not exactly. Despite often being more efficient, electric furnaces are costlier to operate than gas furnaces in a vast majority of cases because those two energy sources are priced differently. In most parts of the country—including here in California—natural gas is far cheaper than electricity. This is one of the main pitfalls of exclusively looking at AFUE as a means of interpreting just how much you’ll pay on your monthly heating bills.

Buying an electric furnace

So, if electricity is that much more expensive than gas, why install an electric furnace? There are several factors that may make an electric system right for you:

  • If your home does not have natural gas, electricity is the next best choice compared to oil or propane furnaces.
  • Electric furnaces do not need an exhaust setup to dispose of byproduct gases.
  • It is possible that renewable energy makes electricity somewhat less expensive in the future. If you have rooftop solar, the cost of running an electric furnace is greatly reduced.

Deciding between a gas and electric furnace

If you’re not sure what type of furnace is right for your home, our recommendation is that you give our team a call. There are several factors to consider when choosing between a gas and electric furnace, not to mention the potential option of installing a heat pump or ductless heating system. During your free in-home estimate, one of our technicians can talk you through your options and help you find the heating system and solution that’s right for your home.

Also, during your estimate, be sure to ask us about our financing on new furnaces and heating systems, available with approved credit.