If you’re trying to pick out a new heating system for your home, one question you’ll have to answer is whether you want a boiler or a furnace. And the first question you’ll Google is, “Which is better? A boiler or a furnace?” 

There’s no one right answer for every person, but once you know the difference between boilers and furnaces, you’ll have an easier time making an informed decision. 

The basic difference between boilers and furnaces is that boilers use water to heat your home, and furnaces use air. 

How A Boiler Works: 

  1. Your thermostat tells your boiler it’s too cold
  2. Your boiler uses gas, electricity or oil to heat water inside the boiler
  3. The heated water/steam travels through your home via radiators or radiant heat flooring, and the heat radiates and warms up your house.  
  4. The cool water is sent back to the boiler, and the process repeats 

How A Furnace Works: 

  1. Your thermostat tells your furnace it’s too cold 
  2. Your furnace uses gas, electricity or oil to eat the air in the furnace 
  3. The furnace then forces the air through ductwork in your home and blows it through vents to heat each room. 
  4. Cool air is “collected” back into the furnace, and then heated again when necessary 

So which is better? 

If you’re already in a home with one or the other, it’s probably easiest and least expensive to stick with what’s currently installed. This is because adding ductwork to a home with radiators — or radiators to one with existing ductwork — will require a lot of construction and therefore money. That doesn’t mean you can’t upgrade (in fact, we recommend it, since modern systems are MUCH more energy efficient), but switching systems is generally costlier. 

That said, there are still cases where making a switch is wise. For example, you may want to keep ductwork for central air conditioning, but make the switch to radiant floor heating via a boiler because it’s more energy efficient than heating your home with furnace air. 

First let’s look at the pros/cons of a boiler: 


  1. Newer models are much more energy efficient than furnaces. 
  2. No drafts! Heat radiates instead of blowing all around. 
  3. Humid air. Cracked, dry skin all winter? Boilers will keep your home’s air moist. 
  4. No loss of energy in ductwork, meaning you don’t spend money to heat the ducts in your home! 


  1. Boilers are significantly more expensive up-front to purchase and install, especially the higher-end models. 
  2. Boilers can leak and cause water damage. 

BOILER SUMMARY: While the upfront cost is higher, the year-to-year cost is much less and boilers are more eco-friendly because they’ll use less fuel to keep your home warm. You do have the risk of leaks, however, which can cause costly water damage. 

Now what about a furnace? 


  1. Less expensive up-front costs. 
  2. Ductwork can also be used for central air, meaning you can stay cool in the summers! 
  3. Furnaces can’t leak water into your home. 


  1. Less energy-efficient 
  2. More yearly costs in fuel
  3. Lost energy in ductwork (you end up paying to heat air you never feel!) 

FURNACE SUMMARY: A furnace is a good option if you want to use ducts for both heating and cooling your home, and if you don’t want a big up-front cost. You’ll spend more, however, in fuel costs over the lifetime of your furnace. That said, you won’t waste any money on water damage from potential boiler leaks. 

So what’s the verdict? 

It’s tough, right? Call the experts at Dunlap’s Energy and get a free consultation. We can help you make the best decision for your specific needs and home. Call us today