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Serving Chicago and Surrounding Suburbs 773.419.0860 |
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Serving Chicago and Surrounding Suburbs 773.419.0860 |
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Conserve Energy and Save Money
Are your energy bills too high? Is your home not
as comfortable as you want it to be? Do you want to do more to protect the
environment? Do you have teenagers at home giving your hot water bill a
beating? Whatever your situation, this will help you to find a solution that’s
right for you. This guide is primarily aimed at homeowners who are thinking of
upgrading or replacing their home’s existing heating or cooling systems. It
also contains useful information for people who are having a home built for
them, and for those who want to reduce their energy consumption in general.
While builders generally offer a standard heating
or heating/cooling package, upgrades to more efficient equipment might be
available. Familiarity with the different systems, fuel options, their
comparative prices and operating costs will help you to review upgrade options
with your builder. Remember to also ask your builder about other energy
efficiency upgrades, which can range from extra insulation to a complete
R-2000-certified home. Before being R-2000-certified, each home is evaluated
and tested to ensure a high level of energy efficiency has been designed and
built into it. There are both financial and environmental benefits to
conserving energy and using it wisely. To help you conserve even more, this
will also direct you to resources that can help you reduce energy consumed for
purposes beyond heating and cooling your home.
A Wise Choice
The options presented will help you to select
heating and cooling systems that meet the needs of both your lifestyle and
your check book. Besides the obvious savings for you that occur by lowering
your consumption, by reducing demand for energy through conservation or, in
the case of electricity, even from shifting consumption to times of lower
demand, together we can lower the market price for the energy that is
consumed. The advantages of investing in energy efficiency aren’t only felt
within your family budget– they are realized in the cleaner environment that
goes hand in hand with more efficient systems and the wise use of energy.
Before You Start
Putting an energy-efficient heating system into a
drafty, poorly insulated house will reduce your energy bills. But you’ll
notice a more dramatic saving, and even make yourself more comfortable, if you
also make your entire house more energy efficient. How? Here are some ideas…
By making your house more energy-efficient, your
heating and cooling systems will work less, and you may reduce the capacity
needed when you replace your systems, which means more savings for you.
Why Energy Efficiency Matters
It’s good for your budget, your comfort and our
environment. Each year you spend hundreds of dollars to heat and cool your
home and to heat your hot water. By installing energy-efficient equipment,
which gives you the same comfort for less energy, you can lower these costs.
Furthermore, the lower you can make your energy costs now, the better off you
will be should energy prices go up – and conservation reduces upward pressure
on energy prices.
Whenever fuels are burned – in your home, in a
generating station to produce electricity, in vehicles or elsewhere – carbon
dioxide, nitrogen oxide and sulphur dioxide are released. These emissions
contribute to environmental concerns including smog, acid rain and climate
change. Reducing energy use lowers the amounts of these emissions and their
impact on the environment. You can help by practicing energy efficiency and
conservation not only in heating and cooling your home, but everywhere at
home, in the workplace and in your transportation choices. Many factors can affect your annual energy bill such as size
and location of your home, yearly variations in
weather, efficiency of your furnace and other appliances,
thermostat settings, number of occupants, and the
local cost of energy.
Are you serious about how to go about
cutting your heating and cooling costs?
Follow these steps:
Heating Units and Controls
There are four common types of heating units:
Most heating systems need air for combustion.
Furnaces, boilers and space heaters that burn fuels need a supply of air to be
able to burn properly, and a vent to the outdoors so that combustion gases can
escape from the house. Electric heaters do not need to be vented. Combustion
is a two-step process: air in, and gases out.
Air in
In the past, there was usually plenty of air
leaking into a house to keep the furnace, boiler or stove burning well. Modern
homes, however, are better sealed and use controlled ventilation, rather than
uncontrolled leakage, to provide greater comfort and energy efficiency. Vents
that supply air for heating units should never be blocked. It is important to
ensure that there is an adequate supply of combustion air available, even when
other air exhausting equipment is in use.
Gases out
Venting used to be done through a chimney. Today,
however, many models of natural gas, oil and propane equipment can be vented
by pipe directly through the wall, which greatly simplifies
installation. Remember that combustion gases
cannot escape from your home unless you provide air to replace them. That’s
why venting problems can often be traced to air supply problems.
Controls
The indoor temperature is automatically controlled
by a thermostat. Two important considerations are location and type. Central
systems are normally controlled by a single thermostat. To achieve proper
temperature control, the thermostat must be located in an area where it will
sense the “average” indoor temperature. Locations exposed to localized temperature extremes (outside walls, drafts, sunlight, hot ducts or pipes, etc.) should be avoided.
Different types of thermostats are available.
Basic types maintain a fixed indoor temperature. However, you can reduce your
heating costs by installing a set-back thermostat which can be programmed to
automatically lower the temperature when no one is home or everyone is in bed,
and then warm up the house before you get home or wake up. Savings will vary,
but a set-back of 3ºC for eight hours daily could reduce your heating costs by
about 5%.
Where space heaters are used, each unit will
likely be individually controlled by its own thermostat – which is usually the
basic type. This allows you to keep unused areas at a lower temperature than
those areas you do use.
Distribution Systems
There are three types of distribution systems.
It is important that a distribution system is
properly designed, installed and operated to ensure maximum energy efficiency
and comfort levels. Try to avoid placing any part of your distribution system
outside of your home’s insulation. This is sometimes done as a simple remedy
to a routing problem, but there is always some heat loss through the wall of
any distribution system. It is better that any losses heat (or cool) you
rather than your attic.
Forced Air
Registers in each room can be adjusted to control
the air flow. Return registers draw air from the rooms through separate ducts
back to the furnace to complete the cycle of air flow through the
house. Leaks in forced air distribution systems
are often ignored because they normally do not cause any obvious damage, but
it is important to avoid/eliminate such leaks. Leaks will affect a
distribution system’s ability to provide comfort in all areas of the house,
and leaks in some parts of the system can result in significant energy loss
and/or condensation-related damage which may be hidden from sight.
Hot water (Hydronic) Heating
Distributes hot water from a boiler to radiators,
convectors or under-floor heating systems in each room. In older homes, large
cast-iron radiators are common. Modern systems feature smaller boilers, narrow
piping and compact radiators that can be regulated to provide temperature
control in each room. Under-the-floor heating systems can be built into the
floors of new and existing homes.
Space heaters
These have no central heating unit or distribution
system. Instead, individual space heaters – such as a wood stove, electric
baseboards, radiant heaters or heaters fueled with oil, natural gas or propane
– supply heat directly to the room. For safety, all space heaters except
electric ones need to be vented to the outside. An appropriately sized space
heater can supply some heat to all parts of a home if the design of the home
allows for natural distribution of heat from the heater location. In most
cases, more than one unit is required to comply with building code
requirements, but multiple units allow you to vary the temperature around the
house.
Energy Sources and Equipment Options
Natural gas
Furnaces in forced air heating systems, boilers in
hot water systems, fireplaces and space heaters can be fueled by natural gas.
It is delivered to your house through an underground pipeline. (It is not
available in some areas.)
Propane
Most equipment fueled by propane is similar to
that fueled by natural gas. In many cases, the only differences are one or two
small components that can often be changed by a registered
contractor to convert a unit from one fuel to the
other. Propane is delivered by truck and stored in a tank on your property.
Gas equipment
Because of their similarities, natural gas and
propane heating equipment are discussed together. The term “gas” refers to
both natural gas and propane. The cost of the two fuels differs, so remember
to check for cost comparisons.
There are three main types of gas furnaces:
Gas boilers have similar ranges of seasonal
efficiency.
Older conventional gas furnaces and
boilers
Some older furnaces and boilers, which are no
longer produced but are still in use, require a continuous liner in a masonry
chimney or a metal “B” vent chimney. The liner is needed because the
combustion gases contain water vapor which condenses on masonry and causes
deterioration over time. About 35 per cent of the heat from the fuel goes up
the chimney with these models.
Mid-efficiency gas furnaces and boilers
These models remove more heat from combustion
gases so that less heat escapes when the gases are exhausted and efficiency is
improved. Depending on the circumstances, they might be vented through a wall
or through a chimney.
High-efficiency (condensing) gas furnaces
and boilers
These models extract so much heat from combustion
gases in order to achieve their efficiency, that they can be safely vented
through a narrow plastic pipe that runs through the wall.
Gas-fueled fireplaces
Gas fireplaces are sometimes used to provide space
heating, though they are often chosen for aesthetic reasons. There can be
significant differences in energy efficiency from one model to another, and the effective efficiency of some
types can be significantly affected by how they are used.
Oil
Oil furnaces and boilers have a burner, a heat
exchanger and a blower or pump. Oil is delivered by truck and stored in a
tank, which is usually located in the basement.
Older conventional oil furnaces and
boilers
Older, conventional oil furnaces and boilers with
a standard burner have a seasonal efficiency generally ranging from 60 to 70%.
Like older, conventional gas furnaces and boilers, they are no longer
produced. However, in an existing model that is working well, the seasonal
efficiency can be improved by replacing the burner with a flame retention unit
– usually a more cost-effective step than replacing the entire furnace.
New oil furnaces and boilers
A typical new oil furnace or boiler has a seasonal
efficiency rating generally ranging from 78 to 86 per cent. Many of these
units can be vented through the wall.
Oil stoves
There are free-standing oil space heaters with a
visible flame now available. There are no efficiency standards for these
products.
 Electricity
Electric resistance systems can consist of a
central furnace or boiler connected to an air or hot water distribution
system, radiant panels embedded in the floor or ceiling or a baseboard space
heating system. Electricity also powers heat pumps. When electric resistance
heating is used in a new home, including as a back-up for an air source heat
pump, the building code requires
the house to be built with higher minimum levels
of insulation.
Heat pumps
A heat pump is usually an electrically-powered
system that can either heat or cool by transferring heat from one place to
another. During the heating season, a heat pump extracts heat from
either the air, ground or water outside the house,
and transfers it indoors. In the summer the direction of the heat flow is
reversed, extracting heat from indoors and transferring it outdoors, to
provide air conditioning. Because they satisfy a
substantial part of your heating needs by utilizing already available heat,
rather than consuming electricity to generate all of the heat you need,
heat pumps are significantly more efficient than
electric resistance heating.
There are three main types of heat pumps:
Air source heat pumps
These most commonly-used heat pumps can provide
all the cooling requirements of a home and most of the heating needs, but they
require an auxiliary heating source during very cold weather. This can be
either an electric resistance or a fossil fuel unit.
Earth energy systems
Also known as ground source heat pumps, these
systems transfer heat from the ground, ground water or surface water and use
it to provide home heating. For summer cooling, the process is reversed. If
desired, earth energy systems can be equipped to provide domestic hot water
year round. Electric resistance heaters may be installed to provide
supplementary heating for the
coldest days.They normally utilize much less
electric resistance heat and offer significantly higher efficiency than air
source heat pumps.
Wood
Some households use wood as their main fuel but
even more use it as a supplementary source of heat. Most of these households
are outside large urban areas where firewood is usually less expensive than
other fuels. The most common approach to wood heating today is a wood stove or
high-efficiency fireplace installed in the main living area of the house. If
the house is
medium-sized and relatively new, this kind of
equipment can provide almost all the heat needed.
If you have an existing masonry fireplace, a
high-efficiency fireplace insert could be a good option. And many models offer
the pleasure of a visible wood fire.
Older or larger houses may need the additional heating power offered by a wood-burning furnace. If your present heating system is a forced air furnace that uses a more costly fuel, you might want to consider an add-on wood furnace. It is installed beside the existing furnace and the duct work is modified so that it can be shared by both furnaces. Combination wood/oil or wood/electric furnaces are options for new or replacement systems. Stoves that burn pellets made from wood or agricultural crops such as corn kernels are also available. Pellets are automatically fed into the burner and the householder simply dials in the required temperature on the thermostat.
When shopping for wood-burning equipment, visit
several wood heat retail stores and discuss appliance selection, location and
installation with a knowledgeable salesperson.Always buy wood-burning
equipment that is certified for safety. It is also
preferable to buy equipment that has been certified
as meeting the U.S. Environmental Protection
Agency (EPA) or Canadian CSA-B415 emission standards. These certified
wood-burning appliances produce one-tenth of the chimney
emissions and one-third higher efficiency than earlier units.
Outdoor furnace
“Outdoor” wood furnaces or boilers are also on the
market. They may appear attractive, because they will burn low cost material
you would not think of putting in an indoor appliance and can burn for long
periods between refueling. However, they can be low on efficiency and high on
emissions.
Solar energy
Like wood, solar energy is a renewable resource.
Solar heating does not involve the combustion of fuels, so it does not produce
environmentally-harmful emissions. It can be as simple as south facing windows
serving as passive solar collectors. Passive solar heating is free and should
be an important consideration in the design of homes. Homes built to high
levels of energy efficiency and designed to make the most use of free solar
heating can save hundreds of dollars a year on energy bills.
Other energy sources
Residential systems are available to generate
electricity from sunlight or wind. In certain situations, such as remote
locations, one of these may be the most practical option. In addition, the
government is establishing standardized processes and technical requirements
which will require electricity distributors to allow customers with qualifying
generation equipment to supplement their utility electricity needs with power
they generate themselves.
Cooling Systems (air conditioning)
Two types of units cool an entire house: a central
air conditioner or a heat pump. If you only need to cool a specific area, a
window air conditioning unit could be your most energy-conserving choice.
Regardless of what type you are considering, remember that models will vary in
efficiency ratings and efficiency has a direct impact on operating costs, so
optimizing efficiency should be a priority. Consider buying an ENERGY
STAR®-qualified model.
Central cooling
If you decide you want to cool your entire house,
you should consider which system to install – central air conditioning or a
heat pump – when reviewing your home’s heating needs. An air conditioner is
actually a heat pump that can only cool. *Remember: your heating decisions can
affect your cooling options.
Duct work for central air
Duct work is generally needed to carry cool air
throughout the house in a central air conditioning system. If you have a
forced air heating system you can usually use the same ducts for cooling. If
you do not have duct work, you can look into installing it or consider air
conditioning technologies that have been developed for homes without ducts.
These alternatives are more costly, so if you are considering them,
investigate your options with your heating/cooling contractor.
Mini splits
Mini splits are systems suited to homes without a
central air-distribution system. No duct work is required. The system consists
of two components: an outdoor condensing unit, and an indoor evaporator and
fan. The indoor section can frequently be mounted on any interior or exterior
wall, and is much quieter than a window unit.
Window units
Window air conditioners are effective if you only
need to cool a specific area of your home. They will cost less to install than
a central air conditioning system. If you don’t have duct work, they might be
your most practical choice. It is important to match the capacity of the
window air conditioner with the size of the area to be cooled. Window units
should either be covered in winter or, better still, removed to minimize heat
loss.
Other Ways to Cool Your House
The following measures will help keep your home
more comfortable:
Hot Water and How to Heat It
There are several water-heating options available
to you. While you are taking steps to save on home heating, don’t forget to
see what you can do to lower your water heating costs. Check with your fuel
supplier for more information, and consider alternatives to your current
method.
Storage-type water heaters
Most homes have storage-type water heaters in
which water in a tank is heated by a gas or oil burner or by electric
elements. Traditional storage heaters have been improved with such features as
through-the-wall venting for combustion units and better insulation, making
them less expensive to operate. Units designed to give even greater efficiency
are now available.
Instantaneous water heaters
Instantaneous water heaters which heat water as
needed and have no storage tank are available, but not widely. They require
little space, but they usually cost more than storage-type water heaters and
more than one unit might be required to meet your needs. For electric
instantaneous water heaters, upgraded wiring is often necessary.
Integrated (combination) hot water systems
Systems that combine space heating and water
heating are becoming more popular. Water can be heated with a boiler or a
storage-tank water heater. The hot water can be used for space heating as well
as domestic hot water needs. Space heating methods include baseboard
radiators, in-floor radiant heating and forced air heating when piped to an
air handler. Some of these systems can also be used for pool and spa heating
and snow-melting applications. Combo systems vary widely in efficiency and
must be carefully designed to give satisfactory service.
Solar water heaters
In solar water heaters, energy from the sun is
collected by solar panels and transferred by circulating fluids to a storage
tank. These heaters are typically used with an electric water heater, or one
fueled by oil, natural gas or propane, which acts as a back-up for overcast
days. Solar collector panels can be mounted on any unobstructed roof, wall or
ground frame that faces between
southeast and southwest. Solar water heaters are
designed to provide between 35 and 75% of your hot water needs, with the
back-up providing the balance.
Replacing Your System
Review your options, consider the pros and cons of
different equipment and fuels, and compare installation and operating costs.
Now get ready to improve your existing system, and it’s time to select a
contractor. Here are some tips:
Your contractor will supply and install your equipment. Proper installation is essential for the safe, efficient and economical operation of your system. Electric equipment must be installed by a licensed electrician and all electrical work must be inspected.
Prices can vary significantly among contractors.
Ask each firm for a written estimate covering the following items:
Use costs (both installed and operating), work
schedule, warranties and service as the basis for your decision. Ask the
contractors you are considering for references, and follow up by contacting
previous customers. Ask what they think about the contractor, fuel supplier
and the options you are considering.
In order to correctly size new heating and cooling
equipment, your contractor must analyze how much heat is lost from your home
in winter and gained in summer. Ask for this heat loss/gain analysis in
writing, including the method used to perform the calculation. This
calculation should take into consideration such factors as the size of the
house, its level of insulation and the condition of windows and doors. If the
heat loss and gain is significant and you haven’t already taken steps to
increase the energy efficiency of the house, now is the time to do it.
Avoid the temptation to simply choose the same
size equipment that already exists in your house without doing a heat
loss/gain analysis. Your home has likely been altered over the years
and the system might even have been the wrong size
at the start. An oversized unit will usually operate below peak efficiency,
and both oversized and undersized units can adversely affect the
comfort of your home. Any installation involving
combustion equipment should include steps to ensure that there will be an
adequate supply of air for combustion and venting, and that other air
exhausting equipment will not cause problems.
Changing Your Water Heater
Size is an important consideration when selecting
new hot water equipment. A larger family is likely to use more hot water. A
“downsized” household – for example, an older couple whose children have grown
up and moved into their own homes – will no longer need a water heater meant
to supply the needs of four or more people. By practicing water conservation –
for example, by installing energy-efficient showerheads and aerators on taps
and using cold water in your washing machine – you can substantially reduce
your hot water usage.
Steps to installing a hot water tank
Contact your local fuel supplier or contractor and
ask for the efficiency ratings of the models you are considering. When you
have selected a unit just big enough to meet your household needs, your fuel
supplier or contractor can arrange for a qualified serviceperson to install
the water heater. If you have an electric hot water tank, wrap it in an
insulating blanket. Make sure the blanket is certified for use on your heater
and is properly installed. Insulate both the hot and cold water lines of the
tank and consider installing a heat trap. Be careful not to insulate the pipes
too close to the flue of a fossil-fueled tank. Ask your fuel supplier about
any water heating cost-saving programs they offer. Some suppliers do some of
the work at little or no cost to you.
Glossary of terms
Here is a quick overview of terms used in this
guide and that you’ll need to know as you gather information about your home
heating and cooling options.
AIR SOURCE HEAT PUMP
A heating-cooling unit that transfers heat in
either direction between the air outside a home and the indoors.
AIR SUPPLY FOR COMBUSTION
The air that a furnace, boiler or space heater
requires to burn fuel.
AQUASTAT
A thermostat that controls the water temperature
in a boiler.
BOILER
The heating unit used with a hot water (hydronic)
distribution system.
CENTRAL AIR CONDITIONER
A unit that cools an entire house by removing heat
from the inside air and releasing it outside.
CONTROLS
Devices such as a thermostat that regulate a
heating or cooling system.
CONVENTIONAL GAS FURNACE OR BOILER
A gas heating unit with an annual fuel utilization
efficiency (AFUE) less than 70%. It exhausts through a masonry chimney (which
should be lined) or metal “B” vent.
COST-EFFECTIVE HEATING/COOLING SYSTEM
One that produces good value for money after all
costs (purchase, installation, financing and energy charges) are considered.
The components of a heating or cooling system that
deliver warmed or cooled air, or warmed water, to the living space.
DOMESTIC HOT WATER
Hot water used for household purposes.
EARTH ENERGY SYSTEM (ground
source heat pump)
A heat pump that transfers heat from the earth or
ground water in cold weather and transfers it to the house through an
underground piping system for space heating, cooling or water heating. The
process reverses in warm weather, and heat is discharged to the ground or
water.
ELECTRICAL RESISTANCE HEATING
Heat produced by passing electricity through a
resistor.
FLAME RETENTION HEAD BURNER
A higher-efficiency burner in an oil furnace. It
produces a hotter flame and operates with a lower air flow, thus reducing heat
loss up the chimney.
FLUOROCARBON REFRIGERANTS
The fluids commonly used in refrigerating and air
conditioning equipment to create the cooling effect. These fluids can damage
the environment.
FORCED AIR
A distribution system in which a fan circulates
air from the heating or cooling unit to the rooms through a network of ducts.
FOSSIL FUEL
A naturally occurring carbon or hydrocarbon fuel
such as natural gas, propane and oil, formed by the decomposition of
prehistoric organisms.
FURNACE
A heating unit that uses a forced air distribution
system.
GROUND SOURCE HEAT PUMP
Another term for an Earth Energy System.
HEAT EXCHANGER
A structure that transfers heat from one gas or
liquid to another gas or liquid. For example, the hot combustion gases in a
furnace to the circulating household air or, in a boiler, to the circulating
hot water.
HEAT RECOVERY VENTILATOR (HRV)
A device used in central ventilation systems to
reduce the amount of heat that is lost as household air is replaced with
outside air. As fresh air enters the house, it passes through a heat exchanger
heated by the warm outgoing air stream and is preheated.
HIGH-EFFICIENCY (condensing) FURNACE OR
BOILER
A heating unit with an annual fuel utilization
efficiency (AFUE) of 90% or more. It has a second stainless steel heat
exchanger that removes additional heat from exhaust gases. Water vapor
condenses as the exhaust cools. The unit vents through a narrow plastic wall
pipe instead of a chimney.
HYDRONIC SYSTEM
A distribution system in which hot water is
circulated through a network of pipes to radiators, wall panels or an
under-floor heating system.
INSTALLED COST
The total of the purchase price and the
installation costs of equipment.
INSTANTANEOUS WATER HEATER
A device that heats water as required but does not
store it. The unit is usually located near the point of use.
INTEGRATED (combo) HOT WATER SYSTEM
A system that provides both space and water
heating from a single heat source.
KILOWATT
A unit of electrical power used to measure the
heating capacity of electric equipment. One kilowatt (kW) equals 1,000 watts
(W).
MID-EFFICIENCY NATURAL GAS OR PROPANE
FURNACE OR BOILER
A gas heating unit with an annual fuel utilization
efficiency (AFUE) of 78 to 82%. Some models exhaust through the basement wall.
NEW OIL FURNACE
Efficiencies (AFUE) range from 78 to 86%. Has flue
gases that may be exhausted through a chimney or a side wall vent.
R-2000
A performance standard for new homes under a
voluntary government/industry program. Builders meet the standard by offering
an integrated package of features designed to meet the R-2000 requirements.
The package includes high insulation levels, air-tightness, heat recovery
ventilation and efficient heating/cooling systems.
RETROFIT
Replacement of one or more components of an
existing system.
SEASONAL EFFICIENCY
A performance rating that considers the heat (or
‘cool’) actually delivered to the living space, the total energy available in
the fuel consumed, and the impact the equipment itself has on the total
heating or cooling load through an entire heating or cooling season. HSPF,
AFUE, SEER and EF are seasonal efficiency ratings.
SEER
seasonal energy efficiency ratio
SETBACK THERMOSTAT
A programmable thermostat with a built-in timer.
You can adjust it to vary household temperature automatically.
SPACE HEATER
A heating unit that supplies heat directly to the
room where it is located and is not connected to a distribution system.
STORAGE-TYPE WATER HEATER
A tank that heats and stores hot water.
TON
A measure of the cooling capacity for central air
conditioners and heat pumps.
Efficiency Ratings: AFUE, COP, HSPF, SEER
& EER
Take a few moments to familiarize yourself with
the efficiency ratings you’ll find on various pieces of equipment.
Boilers and Furnaces
Rating to look for: AFUE
The annual fuel utilization efficiency (AFUE) of
furnaces and boilers measures their performance over a typical heating season.
It takes into account things like on-and-off cycles and heat loss through the
chimney or vent, and is the most useful furnace and boiler rating available.
The higher the rating, the more efficient the unit.
There is a second efficiency rating for furnaces
and boilers and it is known as steady-state efficiency. It is higher than an
AFUE rating but it’s not as helpful. It measures the equipment’s performance
after it has been running a short while and all components have reached their
normal operating temperature. The steady state efficiency of furnaces and
boilers is determined by
comparing the amount of heat that’s available in
the fuel to the amount that is converted into usable heat, but it does not
include off-cycle losses.
Wood-burning appliances
Advanced equipment which is certified as meeting
the EPA or CSA-B415 emissions standard normally exceeds 60% and averages 70%
efficiency. Conventional wood-burning appliances which are not certified as
low emission average 50% efficiency, with a range of 35 - 70%. Although some
wood burning equipment is specifically certified for efficiency, most is not.
Also, most wood-burning appliances are manually
operated, not automatic, and so the practices of the operator will affect the
efficiency actually achieved.
Heat pumps
Ratings to look for: COP, HSPF
Earth energy systems are rated for heating
efficiency by comparing them to electric resistance heat. The measurement used
is called the coefficient of performance – COP – and is determined by dividing
the heat output by the energy input. Since the COP of an electric resistance
heater is 1.0 – which means that the same amount of energy that goes into it
as electricity comes out as heat – any rating higher than 1.0 means that for
the same amount of electricity going in, more heat comes out. Look for a COP
of 3.1 or more.
The heating efficiency rating for an air source heat pump is called the heating seasonal performance factor (HSPF). This is determined by dividing the total heat provided during the season (in BTU) by the total energy consumed by the system (in watt-hours). The higher the rating, the more efficient the heat pump is over the entire heating season. Look for an HSPF of more than 5.9.
Air conditioners and air source heat pumps
Ratings to look for: SEER
A SEER rating, which stands for Seasonal Energy
Efficiency Ratio, tells you the cooling energy efficiency of air conditioners
and air source heat pumps. The rating is determined by dividing the total
cooling provided during the season (in BTU) by the total energy consumed by
the system (in watt-hours). The higher the rating, the more energy-efficient
the unit. SEERs for new central air conditioners and air source heat pumps
currently range from 10 to 17. For room air conditioners, the range is 8 to
12.
Earth energy systems
Ratings to look for: EER
If you want to know how efficiently an earth
energy system can cool, look for the letters EER, which stand for energy
efficiency ratio. EER ratings are determined by dividing the cooling output of
the ground or water source heat pump (in BTU/hour) by the power input (in
watts). Look for an EER of at least 10.5.
Hot water equipment
Storage-type Hot Water Heaters
An energy factor (EF) is used to rate the energy
efficiency of storage-type hot water heaters. Both on-cycle efficiency and
off-cycle losses are taken into account, which makes it a seasonal rating. The
higher the EF, the more efficient the unit. You can expect the following
energy factor ranges for new storage-type water heaters:
A storage-type water heater added to an earth
energy system will normally have an energy factor of 2.7 to 3.1.
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