That big box in the basement

The first thing homeowners do when their heat goes off is call an HVAC technician to come and save them from the cold. Moments before the technician arrives to look at “that big box in the basement”, the homeowner says a silent prayer hoping that they won’t be forced to replace the furnace but instead get off with a modest furnace repair charge.

Hearing the words “replace your furnace” can send shivers down your spine but with today’s high efficiency heating systems and government rebates, the pain is not as bad as you might think. The key with replacing or upgrading your furnace is not only hiring the right HVAC company but also being armed with a little more knowledge about the types and sizes of furnaces so you can have an informed conversation with your HVAC technician.

Single Stage, Two Stage, Modulating … What?

The most popular type of furnace is the gas forced air furnace, which is fueled by either natural gas or oil. When you understand the types of gas furnaces, you’ll be able to better understand the recommendations your technician will make for your home.

There are 3 types of gas furnaces:

Single Stage
Single stage heating systems (sometimes called standard heating systems) have a single gas valve that fully opens to allow the gas to flow into the unit. The gas is either on or off. This means you don’t have as much control over your fuel usage and that can impact your monthly heating costs.

Two Stage
Two stage heating systems have a two-stage gas valve, allowing the system to regulate the amount of fuel it burns. This valve is tied to the thermostat so the entire system operates in sync, making fuel usage more controlled. Two stage furnaces also run longer heating cycles. That means a lower heat level might be on but the blower is running longer providing better comfort. Two stage furnaces also come with variable speed blowers, which helps you hold the line on energy bills without sacrificing comfort.

Modulating
Modulating furnaces have precision (modulating) gas values that adjust gas flow more precisely. These furnaces boost a home’s comfort by more evenly regulating temperatures throughout the home. Modulating furnaces also come with variable speed blower motors which work together with modulating gas valves. With such precise control, they work extremely efficiently. 98 cents of every dollar you spend on gas goes into your home as heat, and you get the best comfort.

Size Counts – How do you know what size furnace you’ll need?

All of the furnaces above come in different sizes or capacities. Some are for small homes and others for large homes. The size of the furnace is critically important because if the furnace is too big for your home’s capacity, the system will wear much faster. That means it will fail much sooner than it should.

Let the expert HVAC technician determine the right size of furnace to best fit your needs. They will measure the ductwork, calculate room volume, identify where your vents and registers are and make the best recommendation.

Being armed with a little more knowledge about furnaces and furnace sizing, you’re now more prepared to have an informed conversation with your HVAC technician … should that big box in the basement start to sputter.

Next Blog in this Furnace Buyer’s Guide Series: Taking the mystery out of government fuel efficiency ratings