A thermostat is a temperature-sensitive switch that turns heating and cooling systems on and off in your home when the temperature reaches a preset limit. Operation can range from simple manual units to sophisticated programmable units that provide enhanced functionality and highly efficient operation.  Thanks to universal compatibility and easy to understand product packaging, choosing a thermostat is simple. This guide will help you understand the different types of thermostats, what you should know when selecting your thermostat and the special features that increase convenience, comfort and energy efficiency.

Selecting a Thermostat
You can select the thermostat you need in 3 easy steps:

• Step 1: Choose the type of thermostat

• Step 2: Identify your heating and cooling system

• Step 3: Select the options that suit your lifestyle
  
  

Step 1: Choose the Type of Thermostat
The two basic types of thermostats are manual and programmable. Both work with a variety of gas, oil and electric furnaces and control air conditioning as well.

• Manual thermostats are typically found in older homes. These units are economical and have simple controls. They offer limited energy savings and comfort, but can work efficiently if you’re diligent about changing settings as the temperature changes. Many older units contain mercury and offer limited energy savings and comfort control.

• Programmable thermostats adjust the temperature automatically throughout the day, saving you as much as 33% on heating costs and up to 15 to 25% on cooling. Advanced models can switch back and forth between heating and air conditioning during seasonal transitions. They have an easy-to-operate digital interface, and newer models are mercury free

Step 2: Identify Your Heating and Cooling System
Product packaging makes selecting a thermostat compatible with your HVAC system simple. Below are a few terms with which you should be familiar to determine capability with your HVAC system. 

• Works with 1 stage heat or cool – For use where you have separate heating and air conditioning units.

• Works with 2 stage or multi-stage heat or cool – For heating or cooling units that have a high and low speed.

• Works with Direct Line Voltage – 110 or 240 direct current power source used in some older homes to power the thermostat.

• Works with 24mV – For use with a fireplace, floor, or wall furnace.

• Zoned HVAC - Heating and/or cooling is individually controlled in different areas from the same HVAC system.

Step 3: Choose the Options That Fit Your Lifestyle
Select a thermostat that allows you to change the settings as often as you need. Programmable thermostats allow you to set different temperatures at different times of the day, providing the appropriate level of comfort while you are home and adjusting to a set-back, or energy-saving temperature, when you're away or asleep.

Many thermostats come preset with a schedule based on a typical household’s energy needs.  For most homes, a pre-programmed thermostat requires no adjustment – simply install and you’re ready.

When determining the appropriate thermostat, you should consider the flexibility you need from day to day. There are three primary options:

• 7-day programming – Allows you to program each day of the week separately. This option is perfect for today’s busy family with different schedules every day.

• 5-2 programming - Allows you to set a standard program during the week while you’re at work and another program for the weekends when you’re spending more time at home.

• 5-1-1 programming – Allows you to set a standard program during the week in addition to separate programs for both Saturday and Sunday. A great option for families with a structured weekend schedule.

• 1-week - Allows you to set one basic program that runs all week long.

Programmable thermostats are also equipped with controls that allow you to manually override the program’s schedule as needed.

Below are just a few of the features you may want to consider. 

• Touch Screen Controls: Simple touch-sensitive controls put the ability to alter settings right at your fingertips

• Selectable Program Periods: Allows you to set temperatures for different time periods and at various points during the day to fit your specific needs.

• Backlit Display Panel: Allows you to see what you’re doing clearly in low- or no-light environments for easier operation.

• Indicator Lights: Some programmable models have a feature that lets you know when the furnace needs a new filter or the battery is low.

• Battery Operation and Backup: Ideal for older homes where the required wiring may not be readily available. For properly wired homes, a battery backup system eliminates the need to reprogram thermostats after a power failure.

• Remote Programming and Controls: Removable interface lets you program the unit in a more comfortable location. Units with radio frequency remote controls can be changed from anywhere in the house.

• Keyboard Lock: Models with a keyboard lock prevent children and others from tampering with established settings.

• Vacation Mode: Allows you to temporarily set your heating and cooling for maximum energy savings while you’re away on vacation and revert back to normal settings when you return with the push of a button.

Setting Temperatures
A common misperception is that a furnace has to work harder to warm a house after the temperature has been set low during the day, eliminating any energy and cost savings. Studies have shown that the energy used to reheat the house is less than that used to maintain temperatures throughout the day at a higher setting, so you do actually save on energy costs by setting the temperature low at night and during the day while you’re away.

In general, setting your thermostat is simply a matter of adjusting your thermostat to the times you are home or away. The chart below is an example of one way to set your thermostat schedule.

Sample Winter Temperature Schedule

Monday Tuesday Wednesday Thursday Friday Saturday Sunday 7:00am 67º F 7:00am 67º F 7:00am 67º F 7:00am 67º F 7:00am 67º F 8:30am 70º F 8:30am 70º F 8:00am 60º F 8:00am 60º F 8:00am 60º F 8:00am 60º F 8:00am 60º F 9:30am 62º F 9:30am 62º F 5:00pm 67º F 5:00pm 67º F 5:00pm 67º F 5:00pm 67º F 5:00pm 67º F 6:00pm 70º F 6:00pm 70º F 11:00pm 62º F 11:00pm 62º F 11:00pm 62º F 11:00pm 62º F 11:30pm 62º F 11:30pm 62º F 11:00pm 62º F