Furnace Installation: Learn Proper Sizing Basics to Choose Right Unit

When homeowners start looking for the right-sized gas furnace to install in their home, they typically run into the “Goldilocks” problem; some are too large, and some others too small, until they learn how to size up the right unit for their home, and trust the professionals from their local HVAC companies in Toronto.

Why is proper furnace size important? For one, an oversized system will not cycle correctly, heating the home too quickly and then shutting down, repeating the cycle more often than needed. An undersized furnace, on the other hand, will need to work longer and harder to pump out enough heat, essentially overworking itself, and causing it to break down sooner than it should. In both, wasted energy and huge heating bills are the undesirable outcome for having the wrong furnace size.

To choose the right-sized furnace, you can download a special system-sizing program online. You’ll need to input all relevant construction data about your home, and the calculations you get are usually more accurate than you’d ever get from sheer guesswork. You’ll need to have your data to be accurate as building codes typically require code-correct installation.

If you have an existing system installed (that is properly sized) and you’re looking for a replacement, you can also use the size data from that unit as a reference. HVAC pros actually use the existing furnace as a starting point for sizing. In most cases, the replacement furnace size will be nearly identical to its predecessor, as the latter is presumed to have been installed in accordance with energy load calculations performed back when the house was under construction.

The BTU method is also determined along with the unit size if you’re looking to replace an aging furnace. BTU stands for British thermal unit, which is used to measure thermal energy output. You can find out the BTU capacity of your existing furnace by removing the top front service panel. BTUs are measured against room square footage; the BTU output rating should be more than enough to cover the entire square footage of your home. Furthermore, BTU per square footage of heated area is also tied to the climate: cooler climates equate to more BTUs.

If all else seems too complicated, leave the recommendations and installation to the HVAC pros. Furnace installation services from companies like Laird and Son, which serves Toronto and nearby areas, can offer you a price estimate and expert advice on proper sizing.

How To Estimate A Gas Furnace Size, SFGate.com
How To Determine The Right Size Furnace, Angie’s List, December 18, 2014
How Do I Determine The Correct Gas Furnace Size For My Home? ACDirect.com
How To Determine What Size Furnace You Need, GasFurnaceGuide.com
How Many BTUs Does A Furnace Need For A House? SFGate.com

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