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…
-
Weatherstrip and caulk to seal air
leaks. You may have to replace
uncontrolled sources of air with
designed sources to ensure proper
ventilation.
-
Increase insulation levels where
appropriate (such as in the attic or
walls) to reduce heat loss in winter
and heat gain in summer.
- Open
drapes on south-facing windows on
sunny winter days so that the sun’s
energy can help heat your home, and
close them in summer to help keep
your home cool.
-
Choose energy-efficient products
when replacing windows and doors.
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:
-
Where appropriate, improve the
insulation and air sealing in your
home.
- Use
this guide to help you decide what
kinds of changes to your heating and
cooling systems will be right for
you.
- Consult with a
registered heating/cooling
contractor
and your fuel supplier before making
a final decision.
Heating Units and Controls
There are
four common types of heating units:
- A
furnace provides heat through a
forced air distribution system.
- A
boiler provides heat through a
hydronic distribution system.
(Hydronic systems are also referred
to as hot water systems.)
- A
space heater supplies heat directly
to the room where it is located.
- A
heat pump extracts heat from the
air, ground or water outside the
house and usually delivers it
through a forced air distribution
system.
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.
- A
forced air system circulates warmed
or cooled air around the house
through a network of ducts. It also
provides a means of distributing
ventilation air.
- A
hot water (hydronic) system
distributes heat through hot water
pipes and radiators.
-
Space heaters, though not
technically a distribution system,
provide direct heat to the room in
which they are located.
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:
-
conventional (with a seasonal
efficiency range of 55 to 68 per
cent)
-
mid-efficiency (78 to 82 per cent)
-
high-efficiency (90 to 98 per cent)
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
-
earth energy systems
-
bivalent 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:
-
Install ceiling fans to circulate
air.
- If
you’re planning for the long term,
plant trees that lose their leaves
in the fall on the east, south and
west side of your house.
-
Close the drapes or blinds on south
and west-facing windows during sunny
summer days to reduce heat gains.
- Turn
off lights and appliances when they
are not in use.
-
Install awnings for patio doors and
windows that face the sun.
- Open
windows in the evening and at night
during the summer months.
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:
- Look
for a registered contractor
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.
- Get estimates
from several contractors.
Prices can
vary significantly among contractors.
Ask each firm for a written estimate
covering the following items:
- The
total cost and a listing of all
necessary work including
improvements to the existing system
and the provision of combustion air
if applicable
- Heat
loss/gain analysis
- The size and
seasonal efficiency of the unit, and
sound ratings if applicable
- Responsibility of
the contractor or homeowner for:
- Obtaining
permits and paying related fees
- Removing and
disposing of old equipment
- Arranging for
such work as installation
of gas supply
- Arranging
necessary inspections
- A
work schedule and completion date
-
Guarantees, warranties and service
contracts
-
Terms of payment
-
Evidence of an electrician’s licence
as appropriate
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.
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.
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:
- Gas
0.56 to 0.86
-
Electric 0.87 to 0.98
- Oil
0.53 to .68
A
storage-type water heater added to an
earth energy system will normally have
an energy factor of 2.7 to 3.1.
