Choosing A Furnace or Boiler
A gas furnace will heat your home for around 20 years, so it's important to choose one that provides the home comfort and efficiency you need. Here are some tips for selecting a gas or oil furnace:
Consider comfort. Many of today's furnaces contain extra features that will make your home more enjoyable. Some extremely efficient furnaces, reach 98% AFUE. Modulating Furnace - means they can vary the output level to provide the quietest and most comfortable indoor temperatures. Also, look for two-stage and variable-speed models that run at different output (capacity) levels to reduce noise and provide a better mix of air throughout the home (reducing hot or cold spots).
Look for the highest AFUE. Annual Fuel Utilization Efficiency - or AFUE - is a measurement of the efficiency of your furnace. An 80% AFUE furnace converts 80% of the fuel into heat; the other 20% is lost up the chimney. Most furnaces installed in the past 15 years are around 65% to 70% AFUE.
Today's minimum AFUE standards vary depending on where you live. In Canada, for instance, 90% AFUE is the minimum. Most rebate and tax credit incentives are tied to heating efficiencies above 95% AFUE.
It's important to ask your dealer about the standards in your region, and what state, federal and local utility incentives are available for purchasing higher-efficiency furnaces.
Don't skimp on the install. With a new home heating system, the installation is key to performance. Make sure you hire a licensed contractor who is going to address your ductwork and other home needs in addition to replacing the furnace. A quality installation will cost more upfront, but it will save problems down the road.
Fan on. The thermostat for your new furnace may have a "fan on' setting. If so, consider running this fan throughout the summer and winter. It will continue to move air throughout the home even with the furnace isn't heating. It's a great way to even out temperatures on multi-level homes and reduce stagnant air. For even better air control, ask your dealer about zoning.
IF you are buying a new boiler for your home heating needs, make sure you select one that is efficient and affordable. Boiler manufacturers are required to disclose how well the boiler produces heat by displaying its AFUE or annual fuel utilization efficiency rating. The higher the rating, the more efficient the boiler in terms of how much fuel gets converted into heat. The minimum rating allowed for boilers varies depending on the type of boiler.
There are several types of boiler on the market, and they differ by the fuel and medium. Hot water boilers heat the home with hot water, while steam boilers heat the home with steam. The fuel source is usually either oil or gas.The minimum AFUE ratings for these boilers are:
Oil fired hot water boiler – 84 percent
Oil fired steam boiler – 82 percent
Gas fired hot water boiler – 82 percent
Gas fired steam boiler – 80 percent
Make sure you understand these are minimum standards, and you can obtain greater efficiency by buying a higher AFUE boiler. More efficient condensing boilers (90 percent plus AFUE) utilize heat from the condensation of water vapor in a second heat exchanger. These boilers have a much higher up-front cost, but they will reduce energy costs over the boiler’s lifetime.