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How to Choose the Right Furnace Size For Your Denver Home

December 02, 2016

Not all furnaces are created equal.

A furnace that’s too big for your home wastes energy and money. It also wears down system components faster. A furnace that’s too small leaves you feeling cold when you need heat the most.

So how do you know what size furnace is right for your home?

To find the right size, an HVAC contractor needs to perform a load calculation, which takes into account various factors to find the furnace size you need.

In this article, we’ll go into more detail about load calculations and the factors that determine furnace size.

Why load calculations are critically important for furnace sizing

Only a load calculation performed by a certified heating expert will give you the correct furnace size for your home. 

The Air Conditioning Contractors of America (ACCA) sets guidelines for load calculations, which are compiled into a guide called Manual J. This is the national standard that HVAC techs use for residential heating and cooling repairs and installations.

These calculations are complicated, but at Plumbline Services, our heating experts are always precise in determining your home’s correct furnace size so that you stay warm, cut costs and conserve energy. 

Turn away contractors who:

  • Do not perform a load calculation.
  • Determine the size just based on your home’s size.
  • Determine the size you need solely by your current furnace’s size. Most furnaces are oversized, so replacing your current furnace with one of the same size would be like replacing an oversized shoe with another shoe that’s just as large. 

Factors that determine furnace size

When computing a load calculation, a HVAC Design Specialist will visit your home to look at these factors:

  • Local climate
  • The home’s square footage
  • How many people live in the home
  • The insulation values of walls, attics and windows
  • Window size and type
  • Home design (Is it an open floor plan? How many rooms?, etc.)
  • Appliances in the home and their heat efficiencies
  • The condition and layout of ductwork

They’ll also take a look at what materials were used to build your house. For example, a brick home is generally better insulated than a home with wood siding, which could lessen the need for a larger furnace. The landscape around the house (like trees and shrubbery) can also impact your home’s insulation, which in turn influences what size furnace you need.

Your HVAC contractor will also take into account furnace efficiency. If you buy a furnace with greater efficiency, it could be possible to use a smaller unit and receive the same amount of heat in your home.

You can tell a furnace’s efficiency through the AFUE (annual fuel utilization efficiency) percentage rating. You can think of the AFUE as the percentage of fuel that’s actually used to heat your home. The higher the percentage, the more efficient the furnace.

Contact a specialist to find the right furnace size (for free)

Thankfully, if you live in the Denver area, you can determine the size you need quite easily—and for free

Just contact us for a free furnace estimate (we perform the load calculation as part of the estimate). 

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