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Home heating systems and heating options: heaters and furnaces

This section focuses primarily on the many aspects of central heating, furnaces, and heaters for homes and businesses. We also provide an introduction to ductless heat pumps for rooms or smaller spaces. The central heating systems we focus on are fixed as opposed to being portable. To find resources on portable room heaters, we recommend you visit a site that focuses on those.

The climate affects the design of homes, such as insulation and the presence of basements. Compared to a home on a concrete slab foundation, those with a basement provide more places to locate a furnace or ductwork.

The majority of this page describes the furnace and heating components within a “split” heating and air conditioning system with ductwork. The term “split” simply means that the major components (on the A/C side, the evaporator coils and condenser coils and compressor) are divided into two cabinets connected by lines, one located inside and another outside. The other alternative is for the major components to be inside one cabinet, or “package”. Once the furnace and heat exchanger have heated the air, it must be moved to the rooms that need heating.

Furnace design and how they work

In a furnace, a fuel is burned and the heat produced goes through a heat exchanger into to the air distribution system for the home or building. The blower and fan and ductwork carry the warmed air to the rooms where it is needed. A vent pipe or flue transfers waste gases to the outside air. Depending on where they need to be located within a structure, furnaces have different designs. These include conventional up-flow, horizontal, and down-flow designs.

Today’s central heating systems are more efficient

On the brighter side, today’s central heating systems with gas are much more efficient than their predecessors. The heating industry uses a rating called the Annual Fuel Utilization Efficiency (AFUE) to measure the efficiency of converting gas into energy for heating. A high AFUE rating means the furnace can derive more heat from each unit of gas. This means both lower costs in utility bills and less environmental impact from emissions. Only twenty-five years ago, the typical gas furnace had an AFUE of about 65 percent. Currently, regulations of gas furnaces require them to exceed 78 percent efficiency. The AFUE range commonly seen is 80 to 95 percent, and the most efficient furnaces have an AFUE of almost 98 percent.

Furnace and central heating maintenance and repair

Maintenance: plan ahead with regular maintenance, reduce the likelihood of emergency repairs, save energy, and prevent buildup of dangerous carbon monoxide.

Northwest Heating and Cooling encourages planning ahead through maintenance to prevent heater repairs. Why? If you wait until your heating system breaks, you will not only have to pay for the parts and labor, but most heater failures happen at the same time for everyone, during the first cold weather or times of intense use, such as the coldest day of the year. Since the repair companies are more likely to be busy then, you will be more likely to pay for an after hours repair or emergency trip charge.

In addition to annual maintenance from your heating contractor, be sure to change all air filters in your heating system according to the manufacturer’s directions. Make sure your ductwork is insulated if it runs through space that is not conditioned (i.e. in an attic instead of below the room ceilings.) Also, have your heating air ducts checked periodically for leaks. Sealing leaky ducts usually saves between 20% and 27% of all heated (and cooled) air, which would otherwise be lost through into un-conditioned space. Overall, skimping on regular maintenance and adjustment of your heating system can cause you to pay more each month on your utility bills due to wasted fuel and electricity.

From a mechanical viewpoint, the main components in a central heating system can last up to 25 years. Due to improvements in fuel efficiency in furnaces, their economic life is much shorter. Twenty-five years also happens to be longer than normal mechanical and economic lifespan of most air conditioners, so this leads to decisions on replacing all or part of your central HVAC system. If you are “on the fence” regarding repair vs. replacing your heating or HVAC system, you will want to talk about this while setting the appointment with Northwest Heating and Cooling.

Ductless heating alternatives

Some situations call for heaters that do not require ductwork. Examples of suitable applications include one-room additions, offices, or garage apartments, and in a commercial setting, motel rooms. Although the equipment costs more than a portable space heater and needs professional installation, fixed ductless heat pumps offer some distinct advantages over portable space heaters. Because of their design, ductless heat pumps: provide heating and cooling with one unit, produce heat more safely than un vented gas portable space heaters and are usually more energy efficient that electric portable (“strip” heat source only) space heaters.

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