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Kevin
Goff
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Serving Lansing, Michigan
and surrounding areas
517-699-7787 Inspections Performed 24/7 including Holidays |
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Links of Interest Conserve Energy 17 Ways To Save Energy
With the rising cost of energy cost, here
are some easy to do tips to help lower your energy bill.
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…
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:
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:
Prices can vary significantly among contractors.
Ask each firm for a written estimate covering the following items:
Responsibility of the contractor or
homeowner for:
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.
Choose the right equipment
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.
AQUA STAT
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.
DISTRIBUTION SYSTEM
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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