While listening or watching to the Furnace advertisements, you must have come across these words; ''single stage, two-stage and variable speed". Ever wondered what does this really mean? If you have no idea what does this mean and if, in your basement, there is still a single-stage Furnace installed, this blog is for you. Let's begin by exploring what these different types mean and what different is made when an upgrade is made.

Understanding the difference between Single Stage, Two-Stage and Variable Speed Furnace

The Single Stage Furnace units, as the name also indicates, are able to operate at only one and fullest capacity of 100% which means a lot of energy is wasted. On the contrary, the two-stage Furnace units have two possible capacities on which they can be operated; 100% or 70%. The variable capacity Furnaces are so far the most efficient and the latest technology in the market. They have the ability to modulate the operational capacity between 40% to 100% anywhere, as the circumstances demand. The variation in capacity of these different Furnace units impact their price tags, their repair & maintenance frequency as well as their durability. Below, we further analyse what benefits the latest technology Furnace units have over the old technology units and why it can be a good choice to upgrade to a two-stage or variable speed Furnace.



- Upgrade to save of operational cost

The purchase of an appliance is a one-time spending, however, the operational cost is ongoing. While the two-stage and variable speed Furnaces are expensive than the single stage units (with variable speed Furnace, almost double the price), the price is compensated on the operational cost. The latest variable capacity models offer up to 30% and more saving on energy bills annually. While the saving may not fully compensate the expense of purchase, there are other convincing reasons to still upgrade to a better efficiency model and one of those reasons is comfort.

- Upgrade to enjoy better comfort

The temperature swings that are created as a cycle ends can create discomfort. With single stage units, this temperature swing is 4 degrees or more. In two-stage units, this difference could be 1-2 degrees. However, the variable speed Furnaces create the most comfortable indoor by creating no difference at all. The indoor is free of hot and cold spots with a variable speed Furnace.

- Upgrade to breathe cleaner

The variable speed Furnace unit has an edge on single-stage and two-stage Furnace when it comes to cleaning the air. Since this type allows longer air cycles, the air keeps circulating through the filters several times a day making it more filtered and cleaner.  

Is upgrading suitable for you?

Which capacity Furnace must be used depends primarily on the type of climate it will be installed in. For milder climates, experts suggest that a single stage or two-stage Furnace works well and this needs the least investment. However, for harshly cold climates, variable speed units work best while offering the most efficient operation. Depending on your climate, the location of the house, the availability and cost of the required fuels and some other factors, a reliable HVAC technician can make the best suggestion regarding whether or not upgrading is a thing you must consider this winter. 

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