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Single Stage Versus Two Stage Furnace: What’s the Difference Between the Two?

this way, that wayWhen you’re buying a new furnace, there are many different features that you need to consider. One decision that can have a big impact on your heating bills, as well as the comfort of your home, is choosing between a single stage and a two stage furnace. Today we’re going to take a look at a single stage versus a two stage furnace and the benefits and downsides of each!

Single stage versus two stage furnace: How they work

Single stage furnaces are designed to meet your home’s heating requirements during the coldest days of the year. They operate at a single, full-powered capacity at all times.

Two stage furnaces, on the other hand, have two separate heating settings. The lower setting is used every time that the furnace turns on and continues to run during milder winter days. When a two stage furnace senses that the low stage is not powerful enough (during colder winter days), it kicks into the higher stage in order to meet the more demanding heating requirements.

Single stage versus two stage furnace: What to expect from each

Single stage furnace:

  • Lower installation costs
  • More fuel consumption and higher energy bills
  • Bigger home temperature swings
  • Louder operation

Two stage furnace:

  • Higher installation costs
  • Less fuel consumption and lower energy bills
  • Only a few degrees in temperature swings
  • Quieter operation

Deciding between a single stage and two stage furnace

A single stage furnace costs less to install than a two stage furnace and will certainly keep your home warm, however it does so at the expense of higher heating bills and wider temperature swings.

The flexibility of a two stage furnace is a great match for the unpredictable weather we have during winter in the St. Louis area. It can save energy during our milder winter days while still keeping our homes sufficiently warm when it’s freezing cold out. The only drawback to a two stage system is that it will cost more upfront, however much of those costs can be recouped in lower operating costs over the system’s lifetime.

Please feel free to contact Jerry Kelly for advice on choosing a new system. We’re here to help you pick the perfect furnace for your home!

If you have any questions about a single stage versus a two stage furnace, or if you’d like a heating system serviced or installed in your home, contact Jerry Kelly, your St. Charles, MO, heating and cooling contractor. We service the St. Louis area, including towns like Chesterfield, Clarkson Valley and Clayton.

photo credit: Lori Greig via photopin cc