Many people believe that they fully understand home furnaces until it’s time to buy a new unit. That’s when most of us quickly realize that finding a good furnace that fits our budget is harder than we anticipated. As a homeowner, your three objectives are to get a furnace that’s affordable, capable of keeping your home warm, and efficient enough to lower your energy bills. Fulfilling these objectives is tricky, but we have a handy new furnace buying guide to help you make an informed purchasing decision.

  1. Do I Need a New Furnace?

When you begin to compare furnaces that meet the three criteria outlined in the introduction, your first decision should be if you need a new furnace at all. In many cases, homeowners pay for a new furnace when their existing unit or heat pump could be repaired. The best way to evaluate your existing HVAC system is to contact your local heating and cooling specialist and ask them to take a look at your system. If you determine that you do need a new furnace, there are four additional questions that you must answer before making a final purchase.

  1. Is This Furnace Energy Efficient?

Every furnace on sale as an Annual Fuel Utilization Efficiency (AFUE) rating is expressed as a percentage figure. The higher the AFUE rating, the more energy efficient the furnace will be, and this will translate into lower heating bills. The AFUE refers to the conversion process that turns fuel into heat over the course of an average year. The most common fuel source for a modern furnace is gas, and the higher the energy efficiency, the more expensive the furnace will be.

The heating and cooling industry is in a constant state of development. The furnaces on sale today are far more energy efficient when compared to furnaces made in the past decade. By law, it is now illegal to manufacture and sell a residential furnace with an AFUE of less than 78%. This is necessary to meet stringent new environmental legislation, but it helps to lower or energy bills too. Back in the 70s, a typical residential furnace would only have an AFUE of 65%. In comparison, a modern furnace could have an AFUE of 97%, but any AFUE over 90% is considered to be a high efficiency furnace.

If you can afford a high efficiency furnace, it is worth the extra investment. The potential savings on your winter heating bills will be recouped in a few years. From that point onwards, you can enjoy lower heating bills for the remainder of the furnace’s useful lifespan.

  1. What is the Furnace Type?

There are two different types of furnace types, but they are both measured with the same AFUE rating discussed earlier. You can purchase a conventional or high-efficiency furnace.

A conventional furnace operates in the AFUE rating range of 80-83%, which is sufficient to meet the minimum standards, but you won’t save much on your energy bills.

A better option is a condensing or high-efficiency furnace that operates in the 90-98% AFUE rating range. This is a far better option to save energy, but the initial cost is much higher.

Dealing with AFUE ratings can get pretty complicated, but there is an easier way to think of them. If you look at an AFUE rating of 90%, you have a furnace that uses 90% of the energy in a useful way, and it only wastes 10% that disappears up the flue. In this example, you would be paying for 10% of the energy that you never receive. Due to the limits of engineering, it would be impossible to manufacture a furnace with an AFUE rating of 100%. But, the closer you can get to that unattainable figure, the more money you will save on your heating bills.

  1. Is the Furnace the Right Size?

Every furnace has a British Thermal Unit (BTU) rating that determines how much heat it can generate per hour. As an example: it would take 1 BTU to heat 1 lb of water to 1ºF. Each BTU is equivalent to 252 calories or 1,055 joules, which is the similar amount of energy that is released when you strike a match!

As you can see, dealing with BTUs can get complicated quickly. To simplify the process, it’s easier to think of them in broader terms related to spaces. In the heating and cooling industry, 25-30 BTU per square foot is considered adequate for moderate climates, and this rises to around 45 BTU in colder climes. If you know your BTU requirements exactly, you can size the furnace accurately and save money.

Ideally, the goal is to save energy by using the exact BTU required for your home. This can be determined with a BTU calculator, input the room width, ceiling height, house length, and other factors to get a precise BTU figure. The best way to deal with your BTU requirements is to contact your local HVAC specialist and ask them about a professional load calculation for your home.

  1. What Features Does the Furnace Have?

There are two main features that can make your furnace easier to use and more energy efficient.

The blower types could be a single speed, dual speed, or a variable speed unit. A variable speed blower is far more efficient because it can be adjusted to the exact heating criteria that you need. Variable speed blowers are becoming the new industry standard, and this is the type of blower you need if you want to maximize your energy savings.

The furnace stage and type are important. There are three different burner types in use today; they are single stage, dual stage, and modulating. The modulating burner is the best option by far because the flame can be set at any point you like. This is a more flexible way to heat your home and keep the temperature constant.

If you want to install a new furnace in your home, consult your local HVAC specialist for expert help and advice today.