The most efficient boiler a homeowner can buy is a condensing or non-condensing boiler, and you’ll want to know the features that create peak efficiency to make a wise choice.
Boilers are rated via Annual Fuel Utilization Efficiency (AFUE), and high-efficiency condensing units begin at 90. What this means is a 90 AFUE-rated boiler uses 90 percent of the warmth created to heat your home, with 10 percent lost through vented gas. Condensing technology is efficient because it allows less heat loss from the boiler’s flame, and the boiler’s water is able to absorb lost heat.
These features allow for an efficient combustion process:
- Heat exchanger – With a larger surface, more heat is created, and fuel is extracted before condensing occurs, so less fuel is exhausted and lost.
- Materials – Heat exchangers manufactured with materials that resist corrosion are ideal.
- Dual function – Often, these boiler models will have a second heat exchanger to increase efficiency.
- Burner – An aspirating burner designed for use with an induced draft fan or a power burner can minimize heat loss.
- Side-wall venting – Boiler temperatures in these models are low, so side-wall venting is ideal.
- Installation – Because the boiler doesn’t rely on a chimney, installation costs are reduced.
It is possible to use a non-condensing boiler; however, these don’t reach the efficiency of condensing boilers. Energy Star recommends an AFUE of 85 for energy savings, and this is made possible by:
- Pilot light control. Continuous pilot lights waste energy, so boilers will generally have electric pilot light ignition.
- Increased insulation. Because boilers have to keep the internal water heated to high temperatures, they tend to lose energy through the boiler tank. A well-insulated boiler casing will decrease these losses.
- Draft control. To further the reduction of flue loss, boilers with draft hoods have a downstream vent damper that helps to control loss. Alternatively, an aspirating burner avoids the need for draft hoods by using an induced draft fan.
Get the most efficient boiler possible by looking for these features. The experts at Arpi’s Industries Ltd.can help you select a boiler that fits within your budget.
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