A new thermostat can help you use your air conditioner and furnace more efficiently and can even automatically change the temperature at predetermined times. We recommend a digital, programmable thermostat for most homeowners, but there are various options that are better suited for some homes.
Programmable low-voltage thermostats are the best option for most homeowners. They are reliable and can provide substantial energy savings. They work with most central heating applications that use electricity, gas or oil.
Simple digital thermostats that cannot be programmed are still available for less than $20, but it is worth paying a few extra dollars for a programmable thermostat. For any of these options, we recommend buying a wired model with battery backup, so your heat or air conditioning will come back on after a blackout and you won't lose your settings.
There are various types of programmable thermostats that are inexpensive and easy to install. They all let you set a lower temperature during cold winter days when you are away and at night while you are sleeping. Conversely, you can set higher temperatures in the summer.
Simple models begin at about $25 and allow four or five temperature settings throughout the day. More complex thermostats with settings for each day of the week cost as little as $35. Hundreds of models are available with options including larger numbers, bilingual modes or touch-screen operation.
Advanced Programmable Thermostats
Manufacturers are continually adding bells and whistles to thermostats that drive the price well into the hundreds of dollars. New models can show indoor and outdoor temperature and humidity and can control a humidifier and dehumidifier in addition to the furnace and air conditioning units. They also provide reminders when it is time to change air filters, humidifier pads or batteries. Other models have lockout settings to keep others from changing the temperature and thermostat programs.
Other options for certain situations include:
The cheapest and simplest thermostats still use a pair of metallic strips to gauge and manipulate the temperature, and they have a basic mechanical dial or lever to change the temperature. Some homeowners who are not comfortable with using electronic devices may choose these old-fashioned thermostats. However, they are often unreliable and slow to respond, potentially leading to discomfort and wasted energy.
Heat Pump Thermostats
Heat pumps have complex heating cycles that could be interrupted by a standard programmable thermostat, potentially wasting energy and even damaging the heat pump. Buy a specialized heat pump thermostat, and have it professionally installed to avoid shorting out the device.
Line Voltage Thermostats
Line voltage thermostats, which may be programmable, are directly wired to the baseboards or radiant heat systems. They are also often unreliable, and are not recommended for other types of heating systems.
A variety of thermostats are available for a wide range of budgets. For programmable thermostats, look for an Energy Star model to make sure you are maximizing energy savings. Also, if you are replacing an old thermostat, it probably contains mercury and cannot simply be thrown in the trash. Find a mercury recycling program in your area.