Let’s say the furnace you have now is just about done. It’s been a long, comfortable ride, but repair bills are mounting, and the fire is slowly dying…so to speak.

Now that you’ve decided to replace it (hypothetically), you’re wondering about which direction to go in – a high efficiency model that promises huge energy savings but costs more, or one with a lower efficiency rating that costs less to purchase and install?

Choices like these aren’t easy, especially since the average homeowner replaces their furnace only once every 12 – 15 years.

What Is Furnace AFUE Ratings

Furnace Efficiency Ratings and What They Mean

Today’s new furnaces range between 80% and 95% energy efficient. These are what are known as AFUE (Annual Fuel Utilization Efficiency) ratings, just for the record.

The higher the rating, the less wasted fuel; hence, the less you pay to heat your home. That means a 95% furnace is more efficient than an 80% furnace, and that’s the one you should buy, right?

Not so fast. That’s because fuel efficiency isn’t – or shouldn’t be – the only determining factor. Here are a few others that also should be considered:

Proper Sizing

Unless your furnace is properly sized, you won’t receive full value from it, regardless of its efficiency rating. An under-sized furnace works overtime which, in turn, leads to added wear and tear. The same goes for an over-sized furnace, which will cycle on and off much more frequently than one that’s properly sized – more wear and tear than necessary, shorter equipment life.

Stage/Burner Type

The stage/burner affects indoor comfort levels and overall furnace efficiency.

There are 3 stage/burner types:

Single-stage
Two-stage
Modulating

A single-stage burner runs at full blast or not at all. So, you’ll have more peaks and valleys of temperature, sporadic comfort and higher-than-needed utility bills.

A two-stage (or dual-stage) burner allows the furnace to run at two different settings: high and low. The low setting is for mildly cold days, allowing it to run more often without using as much energy.

A modulating burner (most efficient) adjusts its flame to any point between off and high, keeping your home’s temperature constant while helping to reduce your heating costs.

Blower Type

The blower is that system component that delivers heat from your furnace to your living spaces. There are 3 different types of blowers:

Single speed: Runs at full blast or not at all

Multi-speed: Runs at 3 different speeds (low, medium, high) depending on the amount of heat called for by the thermostat setting.

Variable speed (most efficient): Can incrementally adjust airflow, just like the modulating burner.

How Optimum Air Can Help

The moral of this blog is that you should seek professional assistance before embarking on a furnace replacement mission. Throughout the DFW area, there’s no one better suited to that task than Optimum Air. We work every day to deliver maximum indoor comfort, all year long. We’re also highly experienced at helping our many customers to reduce their indoor comfort costs.