Choosing the Right Boiler for Your Home

At the heart of every radiant heating system is a boiler, which is responsible for heating water or making steam, usually to radiators. If you need to replace your boiler, it’s important to know which one will best fit your home heating needs. Here are some considerations to guide you in selecting the right boiler for your home.

Condensing versus Non-Condensing Boilers or Furnaces

To understand the difference between the two types of systems, let’s briefly discuss how boilers operate. Both condensing and non-condensing boilers work by extracting heat from fuel as it burns. The extracted heat is sent through an exchanger, which transfers the heat to the water that runs through your radiators or baseboards. Because no fuel-burning system is 100% efficient, some of the generated heat is lost as exhaust.

Operating Efficiencies

With a condensing boiler, the lost heat (exhaust) from the fuel burning process is routed to a secondary heat exchanger, which brings it back into your heating system. By pulling more heat from the fuel burning process, condensing boilers improve operating efficiency by an average of 10 percent more than their non-condensing counterparts.

Fuel Costs

Because condensing boilers operate more efficiently, your fuel costs will be lower.

Boiler Equipment and Installation Costs

Although many homeowners opt to replace their old heating systems with condensing units, some still opt for the older-style, non-condensing boilers because the equipment and installation costs are lower. Non-condensing boilers are simpler systems that are much cheaper to manufacture. Condensing boilers are more complicated and require expert installation by an HVAC professional.

Other Boiler and Furnace System Installation Considerations

From an energy perspective, most homeowners favor condensing boilers, despite their higher initial cost. However, there are a few other considerations for these types of systems:

Condensate Discharge

As a by-product of its operation, a condensing boiler discharges a corrosive condensate. This needs to be neutralized to protect your heating system from corrosion. A condensate neutralizer must be installed to raise the pH of the condensate to a more neutral level.

Equipment Changes

If you replace your non-condensing boiler with a condensing boiler, you may have to change your radiators and piping. This is because condensing boilers operate at a lower temperature, affecting the performance of the heat emitters and distribution system.

Venting Requirements

The venting requirements for condensing and non-condensing boiler systems vary. Non-condensing boilers take combustion air directly from the room, where as non-condensing boilers get it from the outdoors, required a fan-powered PVC pipe that can be terminated through a side wall.