Decision-Making Process for Home Heating

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1. The Four-Step Decision-Making Process for Home Heating

In this chapter, each of the four steps in the decision-making process for home heating are described in detail.

Step 1: Draftproofing and Insulating

It is counter-productive to invest in a new or improved heating system only to allow much of its heat to escape because of an inefficient house envelope that needs more insulation or has many air leaks. To avoid this, take a closer look at where you can draftproof and insulate simply and effectively before having your heating system sized, installed or upgraded.

There are many advantages to draftproofing and insulating. Heating the house will cost considerably less, and you will be more comfortable because of fewer drafts and warmer surfaces, such as walls. Your house will tend to be cooler in he summer too. Another benefit to draftproofing and insulating relates to humidity levels. Dry air in a house during the winter is caused by too much outside air getting in. Although the relative humidity may be high for cold outside air, the absolute amount of moisture (water vapour) this cold air can hold is actually very low. When this air is brought inside and heated to house temperature, it becomes extremely dry.

If the air inside your house feels too dry, one of he simplest solutions is to add moisture, using a humidifier or an evaporator tray. However, the best way to increase humidity levels (and lower heating costs) is to reduce air leakage. In general, most houses that have been tightened do not need a humidifier –the moisture generated hrough cooking, bathing, dishwashing and other activities is more than adequate.

However, with an airtight house the reverse can occur. Making your house more airtight can affect he air quality inside. Unwanted fumes, odours, gases and too much humidity can be trapped inside the house envelope and build up over time to unpleasant levels. One of the best ways to solve this problem is to install a fresh air intake or a mechanical ventilation system that brings in and circulates fresh air without causing drafts. Your serviceperson should be able to provide you with more information.

Insulating, caulking and weatherstripping will reduce the amount of heat needed to keep your house comfortable. If your existing home has not been thoroughly reinsulated and draftproofed, you should consider doing this before changing or modifying the heating system. For more information about draftproofing and insulating, write for a free copy of Keeping the Heat In (see page 58). Whether you plan to do it yourself or hire a contractor, this publication explains he details (including proper insulation levels) and can help make the whole job easier.

To ensure that you get a heating system with the right heating capacity, be sure to draftproof and insulate before you and your contractor determine what size of heating system and equipment is best. In general, oversized furnaces will waste fuel because they tend to operate in frequent, short cycles. They may also decrease comfort because of he resulting excessive temperature fluctuations.

If you are buying or building a new house, insist on the R-2000 Standard. R-2000 homes have high levels of insulation, airtight construction, heat recovery ventilators, energy-efficient windows and doors, efficient heating systems and other design features that cut heating requirements by as much as 50 percent compared with conventional construction. The house is more comfortable to live in, and a high-quality product is ensured. For more information on R-2000 homes, contact NRcan (see p. 59) or your provincial/territorial home builders 'association.

Step 2: Selecting Your Energy Source

The next step is to select the heating energy source that is right for you. Generally, your options include oil, natural gas, propane, electricity or wood. You may also choose a combination of hese conventional energy sources or alternatives, such as solar energy. Your decision regarding the most appropriate energy source should be based on a number of considerations, he most important of which are described below.

Energy Availability

Not all energy sources are available in all areas of Canada. Heating oil and electricity are generally available in most places, but natural gas, which must be delivered by pipeline, is not available in much of the Atlantic region or in many rural and remote areas of other provinces. Propane is available in most parts of Canada and may be used in rural or cottage areas as a substitute for fuel oil or natural gas, although often at a significantly higher operating cost. In many areas, wood is a cost-effective complement o your conventional heating system. Check with your local fuel supplier or electrical utility o find out which energy sources are available in your area.

Cost Considerations

For most homeowners, he major factor in the home-heating decision is cost. This factor will have two major components –the capital cost of the installed heating system and the annual operating cost for energy. Other factors, such as maintenance costs, cleanliness and noise of operation, should also be considered.

Installation costs of various heating systems, depending on whether they are new or retrofitted, include such items as:

  • hookup to gas lines or electric power lines

  • cost of 200-amp service for electric heating

  • storage tanks for oil or propane

  • heating equipment (furnace, boiler, baseboard heaters, heat pump, etc.)

  • new or modified chimney or venting system (if required)

  • ducting system or pipes and radiators

  • thermostats and controls

  • cost of trenching or drilling for earth-energy systems (ground-source heat pumps)

  • labour for installation of any of the above

The capital cost of a heating system can range from as low as $1, 000 for baseboard heaters in a small house to as high as $12, 000 or more for a ground-source heat pump capable of providing heating, ir conditioning and hot water for larger home. Heating contractors or utility representatives can give you an estimate of the capital cost of various systems. Always ask for a firm quote before you authorize any work.

Because of their apparently low initial cost, electric baseboard heaters are used in the majority of electrically heated homes in Canada. Today, with much higher electricity rates, the annual cost to heat such a home has become quite high. After being installed, it is fairly difficult and costly to convert to different energy source and heat distribution system.

The operating or fuel cost of a heating system is determined by the following three major factors:

  1. The annual heating load or heating requirements of the house. This depends on climate, size and style of house, insulation levels, irtightness, amount of useful solar energy through windows, amount of heat given off by lights and appliances, thermostat setting, and other operational factors. Together, these factors determine how much heat must be supplied by the heating system over the annual heating season. This number, usually expressed as Btu, kWh or MJ per year (see page 5 for definition of these terms) , can be estimated by a heating contractor, home builder or utility representative.

  2. Choice of energy source and its unit price. Each energy source is measured and priced differently. Oil and propane are priced in cents per litre (¢/L) ; natural gas in cents per cubic metre (¢/m3) , dollars per megajoule ($/MJ) or dollars per gigajoule ($/GJ) ; electricity in cents per kilowatt hour (¢/kWh) ; and wood in dollars per cord. You must consider the heat content of the various energy sources to determine the most cost-effective energy source for your area. Check with your local utility or fuel supplier for the price of energy sources. Table 2 on page 40 gives the energy content for the various energy sources in the units in which they are commonly sold.

  3. Equipment efficiency. The seasonal efficiency with which the appliance converts the energy source to useful heat in the home is also an important factor in the heating cost equation. For example, if a furnace has an AFUE (see page 4) of 80 percent, then 80 percent of the heat value in the fuel is available. The other 20 percent is lost, mostly up the chimney; thus, additional fuel must be consumed to make up for these losses. Improving the efficiency of the heating equipment reduces energy use and cost.

The combination of heating load, fuel choice and equipment efficiency determines the annual cost of heating. A detailed description of how you can calculate heating costs for various energy sources and technologies is given in Chapter 4, along with typical seasonal efficiencies (AFUE) for a range of technologies.

In the end, homeowner thinking about new heating system must balance the capital cost against the operating cost and make the best financial decision, taking into consideration how energy prices might change in the future. Because annual operating costs (and the differences in operating costs with different technologies) are significant compared with capital costs, an investment in high-efficiency equipment is often the wise choice.

Environment

The effects of energy production nd consumption play an important role in many of today's key environmental problems. Exploration and extraction of fossil fuels in fragile ecosystems, spills and leaks during transportation, urban smog, acid rain and global climate change –all can adversely affect our environment. Each form of energy has a different impact t various points in the energy cycle. No form of energy is completely harmless, although the environmental impacts of some sources of supply, such as passive solar energy, are relatively insignificant.

Heating your home affects the environment in different ways, from gases leaving the chimney, to emissions at coal-fired electricity generating station, to flooding at remote hydroelectric site. The overall environmental impact is determined by the amount and type of energy source your heating system uses.

Selecting the cleanest energy source is within your power, but this is often a complex assessment that may vary among regions in Canada. The combustion of natural gas, propane or fuel oil in your furnace releases various pollutants into the local environment.

Although it is easy to blame pollution on combustion prod-ucts from your fuel-fired heating system, it becomes more complex when electricity is involved. Electricity is clean at the point of use, but it has environmental impacts at the point of generation. In Alberta, Saskatchewan, New Brunswick, Nova Scotia, Prince Edward Island, Newfoundland and Labrador nd Ontario, coal or heavy oil is burned to meet electricity demand during the winter. In the other provinces – Manitoba, British Columbia and Quebec –where winter peak demand is met with hydro-electric power, the environmental impact is much less obvious. However, in some instances, emissions of methane can be high in hydro dam projects. Nuclear power has its own set of environmental problems.

In short, there is no easy solution, but by buying the most efficient system with the most appropriate energy source for your area, you can make a major contribution to envi-ronmental health. And by improving energy efficiency, you reduce greenhouse gas emissions that contribute to climate change. Other approaches that can reduce energy use as well as the impact on the environment include improving insulation and airtightness (while ensuring proper ventilation) , maintaining your heating system, installing setback thermostats and improving your heat distribution system.

Step 3: Selecting or Improving Your Heat Distribution System

Most heating systems today are either forced-air systems or hydronic (hot water) systems. These consist of heating unit (furnace or boiler) , a distribution system (ducts and registers, or pipes nd radiators) and controls (such as thermostats) that regulate the system. Some houses use space heaters and may not have distribution networks.

Forced-Air Systems

By far, the most common type of central heating system used in Canadian homes is the forced-air system with furnace as the heat source. Among its advantages are its ability to provide heat quickly and the fact that it can also be used to filter and humidify household air. It can also provide ventilation and central air conditioning. In addition, the furnace fan can be used year-round to provide continuous air circulation throughout the house while efficiently distributing heat in colder months.

Forced-air heating systems lso have some disadvantages. The temperature of the air coming from the heating registers can vary depending on the type of system. The air can sometimes feel cool (especially with certain heat pumps) , even when it is actually warmer than the room temperature. The effect is much the same as the cooling action of a fan or a summer breeze. In addition, there can be short bursts of very hot ir, especially with oversized systems. Some people may find these characteristics uncomfortable at times. The ductwork that distributes the heat may transmit the noise of the furnace and its circulating fan to every room and may circulate dust, as well as cooking and other odours, throughout the house. Consult your heating contractor for further information.

Hydronic Heating Systems

A hydronic heating system uses boiler to heat water, which is then circulated through the house before returning to the boiler to be reheated.

Oil-fired boilers for conventional hydronic heating systems typically produce hot water at approximately 82°C (180 °F) and are part of closed system.

Hot-water or steam-heating systems once had large boilers and used wrought-iron pipes and massive cast-iron radiators; some of these still exist in older homes. For many years now, installers have been using smaller copper piping, slim baseboard heaters, and smaller, more efficient boilers. Recently, CSA-approved plastic piping has become available as an alternative to copper piping for space heating and service hot-water distribution.

Other Types Of Systems

Apart from the more popular systems noted above, other systems that can be used independently or in combination with the standard systems are also available. These include room space heaters, radiant space heaters and built-in radiant systems.

Room space heaters provide heat directly to the rooms in which they are located and do not have a central heat distribution system. Obvious examples are wood stoves, vented oil-fired space heaters, and electric or gas-fired baseboard heaters.

Some space heaters can also be very effective radiant heat sources, warming solid bodies, such as people, in their line of sight without necessarily having to heat up all the air. Good examples are the new direct-vent gas fireplaces, advanced combustion wood fireplaces and portable electric infrared radiant heaters. If properly located in major living space, a radiant space heater can actually act as an effective surrogate zoning system, lowering the overall heat demands of the house and the final heating bills while making the occupants feel more comfortable.

Built-in radiant systems are generally of two types: hot water pipes in floors and electrical cables in floors, which may also be installed in ceilings. The radiant floor type, becoming increasingly popular, consists of narrow hot water pipes embedded in the floor or laid in the joist space under the floor. Hot water at a temperature of around 40 °C (104 °F) is pumped slowly through the pipes and radiates heat into the house. Thick carpets can reduce effectiveness significantly by acting as insulation. Such a system may be more costly to install and does not appear to offer much in direct energy savings. However, some radiant floor installa-tions may offer comfort benefits, resulting in lower ther-mostat settings and reduced heating bills.

Your choice of heat distribution system may be limited if you have a forced-air or hydronic system already in place. If you have an electric baseboard heater and are faced with high heating bills, you may want to change to another type of system and energy source, even though it can be n expensive undertaking. Although a major constraint is the lack of a distribution system, many homeowners are finding that ir ducts for a central forced-air system or pipes and radiators for a hydronic system can be installed at cost that still makes the whole conversion financially ttractive. Fuel-fired space heaters, wood stoves and advanced, energy-efficient wood-or gas-fired fireplaces can also be effective. Your final choice will probably be based on the answers to one or more of the following questions:

  • How much will the system cost compared with other systems?

  • Will this type of system suit my lifestyle? Will I be comfortable with it? Do I want central ventilation, air conditioning or air circulation?

  • Is there a contractor available to install the system?

  • Is the system compatible with my energy choice?

Step 4: Selecting Your Heating Equipment

After you have selected your energy source options and your heat distribution system, you can begin to consider your alternatives regarding heating equipment and efficiency levels. At some point in your evaluation, you will have to consider whether to upgrade your existing heating equipment or to replace it entirely. A number of things can be done to improve the efficiency and general performance of an existing heating system. You also have the choice of several different replacement models with various efficiency ratings and prices.

Following are some details to consider when choosing your equipment.

Equipment Efficiency And Suitability

Refer to Chapters 2 and 3 for a detailed discussion of your options for oil furnaces and boilers.

Purchase, Installation, Operation And Maintenance Costs

Generally, the more efficient heating systems have a higher capital cost. This must be kept in mind when considering any changes or new equipment purchases. You will want to make sure that the reduction in energy consumption and enhanced comfort will reimburse the improvement costs within a reasonable time. More often than not, they will.

Often, the more efficient systems require much less house air and may not even need a chimney but rather can be vented out the side wall. This makes them safer and more compatible with irtight housing. Finally, high-efficiency heating equipment can be an additional marketing attribute if you want to sell your house.

Servicing And Guarantees

It is also important to know the causes and frequency of servicing your system, the price of parts, cost of servicing, and details of guarantees and warranties, such as the period covered nd if parts and labour are included. If you are uncertain about a particular model, ask the seller to give you the names of people who have had one installed.

Energy Efficiency Standards

The Government of Canada has implemented energy efficiency standards for some heating equipment and other energy-consuming appliances and products. Various provincial governments have introduced energy efficiency standards, and other provinces have stated their intention to follow suit. Generally, these standards establish the minimum acceptable energy efficiency for specific types of heating equipment. After the standards re in place, low-efficiency models that do not meet the standards are no longer allowed on the market in that particular jurisdiction.

Availability

Depending on where you live, you may have some difficulty finding the type of furnace, heat pump or boiler you want. This is because the manufacturers 'distribution networks may not be fully developed for all models in all parts of Canada or because certain models have been discontinued due to government minimum-efficiency standards.

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Source: Natural Resources Canada (NRCan) - Office of Energy Efficiency