Thermostats for efficiency and comfort

EASY$ TIP SHEETS
Energy Advice Saving Yukoners Money
Selecting a thermostat
Thermostats for efficiency
and comfort
Types of thermostats
Regardless of the type of heating system you have in your home,
• Line-voltage thermostats
the thermostat plays an important role in ensuring your home is
Quick Links
• Low-voltage thermostats
Thermostat options
• Mechanical
• Electronic
• Programmable
• Special-purpose thermostats
Thermostat location
Recommended thermostat
settings for heating
comfortable. Your thermostat determines when your heat comes on
and off, what temperature your home will be heated to, and it can
help reduce your heating bills. Essentially, the thermostat is the
“brains” behind your heating system.
Selecting a thermostat
When choosing a thermostat, look for the
ENERGY STAR® symbol. ENERGY STAR®
qualified thermostats save energy by
offering four convenient, pre-programmed
temperature settings – settings that try to
anticipate when it’s convenient for you to
scale back on heating or cooling. You can
program the thermostat for your particular
schedule to reflect when you wake, leave
and return to your home and go to bed. At a minimum, these thermostats allow
you to set two different programs for your
weekday and weekend schedules. Some
of these thermostats will allow you to set
a different schedule for every day of the
week. Other features may include: digital,
backlit displays; a reminder when it is time
to change air filters; and smart logic that
allows the thermostat to “learn” when to
start heating so that your house is up to
temperature at the time you want.
Goal and
Summary
This Easy$ tip sheet
describes different types of thermostats and provides
advice on selecting and
operating a thermostat in a way that meets your needs.
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Types of thermostats
There are two basic types of thermostats: “line-voltage” and “low-voltage”
with a number of options for each type.
Line-voltage thermostats
Line-voltage thermostats are used to control unitary heating systems, such as
baseboard and radiant systems. The thermostats are installed in-line (in series)
with the heater, usually at 240 volts. The full current going to the heater also
goes through the thermostat, causing it to heat up when the heater is on. This
may cause the thermostat to sense its own heat and shut off before the room
is comfortable. Line-voltage thermostats are simpler to install and less
expensive than low-voltage thermostats.
Low-voltage thermostats
Low-voltage thermostats are used with gas, oil and electric central heating
systems, zone valves in hot water heating systems, and electric unitary
systems where better control is required. Low-voltage thermostats operate at
24 volts, rather than 240 volts. They are more responsive than line-voltage
thermostats, provide more accurate control and are more adaptable to
programmable controls.
Thermostat options
Whether your thermostat is line-voltage or low-voltage, there are three general
options to choose from.
Mechanical
Mechanical thermostats are inexpensive and easy to install. Thermostats with
mechanical operators (i.e. not electronic) have either a bi-metallic strip or a
vapor-filled bellows to react to temperature change. Some are relatively slow to
respond, which may result in larger temperature swings above and below the
thermostat set point.
Electronic
These thermostats use electronic rather than mechanical components to
sense temperature and control the heating system. They are available in both
line-voltage and low-voltage models.
They can provide accurate temperature control and react more quickly to
temperature changes. Many electronic thermostats have added features such
as automatic setback and programmability. This makes them generally more
expensive than mechanical models.
Programmable
Programmable thermostats automatically adjust the temperature set points at
pre-set times. When you pre-set your desired room temperature to correspond
to your daily activities you can save energy because the thermostat can be
pre-set to automatically turn down the heat at night or when the home is
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empty and turn up the heat when you are home. Models range from simple
clock-like thermostats that provide day and night temperature settings, to
electronic models that let you set different day-of-week and time-of-day
temperatures.
If you have a unitary “packaged” heating system, such as baseboard heaters,
the Canadian Electrical Code requires a thermostat be placed in each room. If
you find that it is too expensive to install a programmable thermostat in every
room, you can start by installing programmable thermostats only in large
rooms that have a great deal of activity, like a living room or family room. This
way it can be programmed to be on during active times and turned down at
times when the room is empty.
Special-purpose thermostats
Special-purpose thermostats have features designed to work with specific
types of equipment. For example, two-stage thermostats are used for hybrid
heating systems using two fuels, such as electricity and oil, to turn on the
backup heating system when the primary system cannot cope with the
demand for heat. Heat/cool thermostats are used for homes with summer air
conditioning. Some thermostats allow you to switch on the furnace fan from
the thermostat to circulate the air in your home in the winter or summer.
Thermostat location
Thermostats should be placed about 1.5 metres (5 feet) above the floor,
centrally located on an inside wall. Never install thermostats in areas subject to
drafts, direct sunlight or sources of heat such as warm air registers,
refrigerators, ranges or other appliances. All of these factors can inadvertently
affect the thermostat by causing it to read the actual room temperature
incorrectly, not enabling it to respond appropriately.
Recommended thermostat settings for heating
Recommended thermostat settings provide comfort and avoid overheating.
Thermostats in rarely-used rooms can be set lower than those in major living
areas, but should not be set so low that excessive condensation forms on the
windows. Setting the thermostat back from 21°C to 16°C at night can result in
energy savings of up to ten per cent, depending on where you live.
Remember, cranking your thermostat up to 30°C, for example, will not heat
your house any faster. Your heating system will work most efficiently if you set
the temperature where you want it for long periods of time (8 hours).
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This Easy$ tip sheet is provided by the
Energy Solutions Centre.
If you have additional questions or
comments, please contact the Energy
Solutions Centre:
Phone: (867) 393-7063 or toll-free from the
communities at 1-800-661-0408 ext. 7063
Mail: Box 2703 (EMR-206),
Whitehorse, Yukon Y1A 2C6
Web: www.esc.gov.yk.ca
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