While “central” heating systems are designed to distribute heat throughout your home or workplace, “space” units are primarily used to provide conditioned air to the room or section of the building in which they are located. “Space” heating units can be freestanding or built into a wall and offer a variety of fuel choices. They may reduce demand on central systems, but their efficiencies vary widely. Regardless of which types you may be considering, to maximize efficiency you will want to be sure to look for ones with high efficiency ratings.
If you heat with wood, or plan to heat with wood, the Department of Environmental Conservation offers some health and environment considerations and the Department of Forests, Parks and Recreation offers some resources on safety. You can also find information related to wood heat and indoor air quality at the Department of Health.
Some examples of space heating:
- Stoves are standalone units. The technology and design of these units has improved, and newer models are usually much more efficient than before, whether fueled by wood pellets, firewood, propane, or gas. These models typically provide more heat from the same amount of fuel and produce lower emissions and creosote. Built-in fans or blowers can help circulate the warm air to other parts of the building. To maximize efficiency, be sure to size the stove correctly for the space you are heating. The type of wood, how dry it is, and the stove design can all contribute to the efficiency of wood-burning units. There are similar considerations for pellet stoves.
- Portable Heaters can easily be moved from room to room as your needs change throughout the day. These are usually electric resistance heaters that are not very efficient.
- Wall Units are fixed in place and may be used to supplement heat in a particular area. If fueled by kerosene, gas, or propane they need to be vented directly to the outside. Electric resistance wall units do not require venting. Electric wall-mounted heat pumps are typically more efficient than electric resistance units and can be used for both heating and cooling.
- Fireplaces are a wonderful focal point for a room, but are very inefficient at heating because most of the heat goes up the chimney. In fact, large amounts of the heat generated by a central heating system can be lost when a fireplace is burning because it pulls cold air in through leakage points in the building. It's best to use wood fireplaces when the central heating system is not needed. Glass and metal doors and heat shields are common ways to help reduce air leaks, as is making sure the damper is closed whenever the fireplace is not in use.
A fireplace insert can make a big difference in cutting down drafts and directing the heat to where you want it. If you are not going to add an insert or use your fireplace, you may want to use insulation to block your fireplace’s chimney and cut this source of heat loss.
- Masonry Heaters are also known as "Russian," "Siberian," and "Finnish" fireplaces. They typically produce more heat than many other wood- or pellet-burning appliances. Masonry heaters include a firebox, a large masonry mass (such as bricks), and long, twisting smoke channels that run through this mass. A small, hot fire built once or twice a day releases heated gases into the long masonry heat tunnels. The masonry absorbs the heat and then slowly releases it into the house over a period of 12 to 20 hours. Because most of the heat from the fuel is transferred to the masonry and slowly released into the room over the day, this type of heater typically does not need to be loaded with fuel as often as other types of wood-heat appliances. A wide variety of masonry heater designs and styles are available. Larger models resemble conventional fireplaces and may cover an entire wall. Smaller models take up about as much space as a wood or pellet stove. In addition to their expense, masonry heaters may have another “disadvantage” when compared to conventional wood stoves and fireplaces—they cannot provide heat quickly from a cold start and they can overheat a building on an unanticipated sunny day.
- Outdoor Wood Boilers are located outside a building’s thermal envelope and tend to be less efficient than other wood-heat systems. Older models have been found to emit air pollution and Vermont requires new outdoor wood boilers to meet specific air quality standards, which you can learn about at the Department of Environmental Conservation.
Electric resistance heating has gradually been displaced in Vermont, due to its relative inefficiency and high cost. These older heating system types include electric baseboard heaters, electric furnaces, electric thermal storage and electric wall heaters. They can be considered "central" or "space" heating systems, depending on whether they are controlled by a central control or by controls located in each individual room. If you heat with electric resistance, you may benefit from a switch. An energy assessment completed by a qualified energy professional can help identify options for saving energy in your home or business.
- Space heating may provide comfortable temperatures in the rooms you use most often and save the cost of heating parts of your home you rarely go into
- In "shoulder" seasons, space heating may warm up a room quickly and save wear and tear on your central heating system
- It may be easy to upgrade or change space conditioning units to take advantage of the latest technology
- Stoves and space heaters may take up floor space and make a room feel small.
- Handling and/or storing stove fuel, like firewood or pellets, in your living or work space can require additional clean-up.
- Stoves can contribute to indoor air pollution.
- Older stoves and fireplaces may emit significant amounts of particulate matter. Newer, EPA-certified models contribute far less particulates and other pollutants to the air and are more energy efficient.
Some Next Steps
One size or type definitely does not fit all when it comes to heating and cooling. Learn more about the current line-up of EPA Certified wood stoves, heat pumps, and other space heaters before deciding whether it is time to upgrade and which one(s) are right for you.
You may also want to visit the following link to learn more about the current line-up of ENERGY STAR® certified Heating & Cooling products:
Visit the pages below to learn more about Heating & Cooling: