Subscribe for e-mail

Sunday, January 20, 2008

Heating Systems

Heating SystemsDepending on your geography, special considertion should be given to heating your new home. Important items to consider are energy costs, air quality and safety. Since it's a costly installation to any new home it makes good economic sense to look carefully at energy efficiency. Heating alone can account for more than 40 percent of your household energy costs, for larger homes and families, it's as high as 65 percent.

The first thing you should do is find out how much heat will be required to adequately and efficiently heat your new home. The heating requirements or "heating load" (as industry professionals say) of a house depends on climate, size, and style of house; insulation levels; air tightness; 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 put into your home by the heating system over the annual heating season.

To make it simple, this number (usually measured as BTU per year), should be determined by a competent heating contractor because it involves measuring the house (windows included), checking insulation levels, maybe even doing a blower door test, and running calculations to determine how much heat will be needed in the specific climate you live in. Once this is determined, it is up to you to decide the preferred heating system for your home and what you want it to run on. Oil, gas, wood and propane are a few options.

The following is a list of the types of heating systems available, including helpful tips about their running costs and energy efficiency to help take the heat off of choosing the right system for your home.

Types of Heat

Basically there are two ways in which you can have your home heated: radiant or convective heat. Radiant heaters heat the object rather than the air surrounding it, while convection heaters fill a room with warm air by transferring heat from one object to another using moving air or water. The design of your interior home will have a great impact on which form of heat is best for your home. For homes with large open spaces, open stair wells and high ceilings, radiant heaters work best, because they ensure that you and your family are warmed, not the open space surrounding you. If your home has lots of enclosed and well insulated rooms than convective heat, is the heat for you, because it's very easy to control once you've had your home properly zoned.

Deciding Between Central Heating and Space Heating

Before you decide whether you want central heating or space heating, you need to figure out which areas of your home you want to heat, how large the rooms are and how long you need to heat the rooms for. By creating zones in your home, you give yourself the flexibility to heat each zone individually, which is the key to energy efficiency. Whether you choose to use space heaters or a zone central heating system, both systems are preferred over using a whole house central heating system, because that system will heat every room in your home regardless of whether you using them or not.

Types of Heaters

Central heating systems/Forced Air Heating
The majority of central heating systems used today are either forced warm air or hydronic (hot water). It's a standard setup that consists of a heating unit, a distribution system, and controls, such as thermostats, that regulate the system.

There are several types of central heating systems to choose from:

Forced air systems (convection heaters) consist of a furnace that heats the air, a fan which blows the hot air through a distribution system of ducts and controls (thermostats). What makes this system popular is the fact it provides heat quickly and its ducts can also be used to filter and humidify the air in your home and provide central air conditioning. The downside to this system is that the fans and ducts can be noisy and require maintenance.

When it comes to fueling your furnace you can use natural gas, electricity, liquid propane and oil. A gas furnace is considered the most efficient forced air system, especially condensing gas furnaces, which release latent heat when water vapor is condensed. Oil furnaces are somewhat less efficient because they produce only half as much water vapor and therefore aren't good for condensing processes. Electric furnaces are 100% effective, but very expensive to operate and difficult to zone. Cost for a basic six outlet system starts around $2500.

For greatest efficiency you should make sure that the system has a high star rating (4-5 stars on the Energy Rating label), zoning options, electronic ignition, thermostat with programmable timer, well insulated ducts and positive close-off registers.

Hydronic heating operates when water is heated in a boiler (generally by oil or gas) and then circulated around the home to radiator panels (mounted under the floors), skirting board convectors or fan coil convectors (commonly referred to as baseboards) that heat the room by convection and radiation. Each panel has its own control valve, so you can control the temperature in each room. Most systems run quite quietly and will not dry the air in your home. Most systems start around $5500.

For greatest efficiency the system you choose should have a low water content boiler, quick response panels, well insulated pipes and individual controls/thermostats for each room.

An Electric heat pump works by moving existing heat from one area to another in one of three ways - air-to-air, water-to-air and ground-to-air. Air-to-air uses a condenser which absorbs heat from the outdoor air and transfers it to an indoor heat exchanger and then it is circulated throughout your home. A water-to-air pump absorbs heat from ground water or surface water such as a nearby pond. One of the best ways to go is ground-to-air, also known as a geothermal system. This system uses underground loops to absorb heat from the earth. - Mother Nature's most naturally-renewable form of energy - so it's plentiful and requires minimal electricity to circulate it. The advantage of a heat pump is that it has both heating and cooling capabilities in one unit.

Electric thin-film heating are when thin films are installed in the ceiling, in wall panels or under floor coverings to give radiant heat. It operates on "peak rate" electricity and is controlled by a thermostat. Cost for electric thin-film heating starts around $35/m2

For greatest efficiency be sure your home has adequate insulation against heating film, programmable timers (to cut back on your electric bill) and individual thermostats for each room.

Space Heaters
Space heaters are designed to heat a zone, rather than your whole home (in some cases, wood heaters can produce enough heat for a whole home). By installing individual space heaters in different zones in your home, you'll allow yourself the best control over the temperature in your home.

There are several types of space heaters you can choose room:

Gas space heaters produce convective or radiant heat by using natural gas. These units can be mounted on either internal (fitted with a vertical flue) or external walls. Units are available that heat from 30m2 to 120m2 and start around $600.

For greatest efficiency using this system be sure that the heat outlet is at floor level, it has an electronic ignition, a flue and remote thermostat.

Reverse-cycle air conditioners are electric convection heaters which extract heat from the outside air and deliver it into your home using a compressor and fan. A big benefit to using this system is that in the summer it delivers cool air. This system is very flexible and can be installed in a wall or window, as a split system with the compressor outside and the console unit mounted inside and as a multi-split system which has more than one internal unit hooked into the external unit. It comes in various sizes and starts around $500. Word of caution - since the system itself is exposed to the outdoors, areas where the temperature drops below 5 degrees can decrease the amount of heat the systems outputs.

For greatest efficiency, purchase a system that has adjustable louvres and a programmable timer.

Electric space heaters/panel convectors are available as convection or radiant heaters, which use "peak rate" electricity. Because these systems can be very expensive to operate, they should be used in rooms that require only short bursts of heat like the bathroom or bedroom. Because their heating capacity only reaches 70m2 it is not capable of adequately heating the main rooms in your home. Cost for these heaters starts around $200.

Solid fuel heaters are available as convection or radiant heaters, which burn wood, briquettes, coal, etc. The top heaters in this class are air tight "slow combustion" heaters, boilers and furnaces, which all require a flue. How well these heaters perform depends on the quality of the wood and method of operation. Cost for these heaters start around $800.

Fireplaces add a wonderful touch to home and hearth, but is one of the most inefficient ways to heat a room. Since heat rises, the majority of air warmed by the fire goes out the chimney - leaving you still snuggling up next to the fire. But isn't that the point of having one - so if your budget allows, indulge in a fireplace or two. The cost to have a fireplace installed depends on the size and materials used, but it's a safe bet to say around $5,000.

Portable Alternatives

If you're looking for a way to cut costs with certain rooms in your home like spare bedrooms, extra bathrooms, enclosed patios, you might want to consider purchasing portable heaters, rather than adding an extra zone to your home. There are several heaters to choose from - electric radiators, electric fan heaters, electric natural convection heaters like oil-filled heaters, portable gas heaters and kerosene heaters. Keep in mind that these heaters are space hogs and can't be blocked - so you'll need to find them a safe home.

Size/Cost Really Matters
Once you've decided on the system you want to use, then you need to figure out the size of the system you need to properly and efficiently heat your home. Picking the right sized heater is essential if you want your home to be comfortable and affordable. Use your head when it comes to heating.

Choosing a heater which is too big, will not only cost more, but it will not operate efficiently or give your home that "cozy" feeling. The same is true if your heater is undersized. That's why determining your home's "heat load" is so essential.

While it may seem easy to cut corners and say a few dollars on your heating system, keep in mind that the purchase price doesn't equal the cost of ownership. High-efficiency systems will have a higher initial price, because of the advanced technology involved, but the money you save in energy costs can pay for the difference in just a short time. For example a geothermal system can cost 30-50 percent more than a standard forced-air furnace but the energy savings can pay back the difference within three years (within seven years, the system will be paid for), not bad for a system with a life expectancy of three decades.

More Than Just a Heater

Keep in mind that no matter how good a heating system you buy for your new home - none of that matters if your home isn't properly designed to keep the heat in . Look at it as designing a heating package. That package should include not only a heating system that fits your home and lifestyle, but a house with well insulated ceilings, walls and floors, tightly sealed windows and doors, and proper zoning of living and sleeping areas. So many times the bedrooms aren't properly zoned and you end up with the "sauna room" where you're forced to freeze out other zones to take the heat out or the "ice box" room, where you're forced to spike heat in another zone to accommodate the chill. These kinds of mistakes can be very costly and uncomfortable, so think of each room individually and consider its usage at all times of the day.

Hot Water Heating Systems

When it comes to deciding how to heat your hot water, you first need to determine how much hot water your home will utilize on a daily basis - showers, dishwashers, washing machines. Then you'll need to decide how to fire up your hot water - solar, gas or electric. With basically three popular choices available, choosing your hot water heating system should be no sweat.

Tankless Water Heaters
Have you ever had a blast of cold water in the shower because the hot water ran out - chilling experience. With a tankless water heater, you'll enjoy an endless supply of hot water - and lower energy bills. Tankless water heaters (also called "instantaneous" or "on demand" water heaters) consist of an electric or gas heating element enclosed in a small module. Instead of warming a large amount of water stored in a tank, a tankless unit heats only the water that flows through it.

Almost immediately when you call for hot water - via the faucet, dishwasher, washing machine - the module senses the change in flow and pressure and the heating element immediately switches on. Stop calling for water and the heaters stops immediately.

The benefits of using a tankless water heater is that it's much smaller than a tank water heater and smaller "point-of-use" water heaters can be installed under a faucet or inside a bathroom or kitchen cabinet. As for longevity, a tankless heater will live twice as long as a tank heater - simply because there's no tank to be rusted.

The biggest drawbacks to using a tankless water heater is the price which averages around $1,500 for just the unit. and the maximum flow rate - basically how much hot water can be used simultaneously. Big families who need to run two showers at the same time, plus a load of laundry won't be able to. What's new - there's an on-demand water heater that has digital temperature controls with sensor, which literally checks the water temperature thousands of times a day.

Tank Water Heaters
The first decision in choosing a new tank-style water heater is usually the fuel source. A natural gas unit will cost less to operate than an electric model. Size and efficiency really matters when it comes to choosing your water tank. If you tend to use a lot of hot water at certain times of the day - say in the morning when everyone takes a shower - you'll want a model that has a higher first-hour rating (how much hot water the unit can produce in one hour). If you don't want to worry about when or how much water you're using than you'll want a water heater with a fast recovery rate to make sure you never run out of hot water. Most tanks range in size from 20 to 80 gallons.

Solar Hot Water Heating
Using solar energy to heat domestic hot water is cost-effective no matter where you live and you can expect it to provide 50-75% of domestic hot water needs. This active system uses collectors (thermal panels) to gather the sun's energy, which is then used to preheat water entering a domestic hot water heater. The gas burner or electric elements in the water heater provide a back-up heat source - primarily during the cooler months and on cloudy days. The hot water is piped to faucets throughout your home in the same fashion as a traditional water heater. Most local building codes require homes using a solar water heater to have a conventional heater as a back-up, because climates can change quickly and dramatically. The cost of a solar water heating systems ranges from $1,500 to $3,000.

Source thehousedesigners.com

0 comments:

Related Posts