As with any complicated piece of technology it is important to find the one that is right for you. This means finding the model that is in your budget and that meets your specific requirements. These comments are especially applicable to digital programmable thermostats. They are complicated devices that range in price from just $20 to $400. Moreover programmable thermostats have numerous functions not all of which will be necessary for your home.
Types of thermostats
The cheapest type of programmable thermostat is a 1 week thermostat such as the Honeywell RTH221B that costs about $20. These devices have only 1 program to set up. They are suitable for retired people and people who work from home that keep regular hours.
The next step up is a 5+2 device that has one program for weekdays and one for the weekend. After that there are 5-1-1 thermostats that have one program for weekdays, one for Saturday and one for Sunday. Such thermostats as the Lux Products TX1500E are thus suited for people with ‘9 to 5’ jobs who like to keep different hours at the weekend.
Finally, there are 7 day thermostats that allow the user to set up a unique program for each day of the week.
All good programmable thermostats whether 1 week or 7 day should have 4 periods to set up per program. This is important as it allows you to set the thermostat to start the HVAC in the morning; have it go off while you are at work; have the home comfortable for when you return from work; and finally to turn down the heating/cooling while you are in bed.
Compatibility
There are a variety of HVAC systems employed in homes. It is stating the obvious to say that you should always check that a thermostat that you intend to buy can actually regulate the heating and cooling systems you have. Generally speaking Honeywell thermostats are the most compatible as they can control 2 stages of heating and 2 stages of cooling. If you have a heat pump it might be worth buying a programmable thermostat designed specifically for heat pumps such as the Lux Products HP2110.
Display
One thing you will need to decide is whether you want a programmable thermostat with a touchscreen display. They are often easier to program but they generally cost slightly more.
Nearly all thermostats show the time and set point temperature. Better thermostats also have filter change and battery change warnings. The Lux Products TX1500E and the Honeywell TH8321 also display the relative humidity in a room.
Some thermostats such as the Hunter 44860 can be changed to show the display in French, English or Spanish. If English is not your first language this can be important for you.
Functions
Digital programmable thermostats essentially turn the heating and cooling off at certain times of the day and night to prevent waste and thus save money. Other functions while useful are not as fundamental to energy efficiency.
One function that might be important for you if you live in a climatic zone that gets very hot or very cold is swing control. This is a function that lets the room temperature fluctuate within a specified range to stop the air-con or furnace continually clicking on and off and wearing out prematurely.
A function that does a lot to stop people fiddling with the settings is adaptive intelligent control. This function uses PID technology that continually makes small adjustments so that the thermostat pre-heats or pre-cools a home so that the set point is reached at the start of a program. This means the home is always the desired temperature when you wake up or return home.
Reviews
Finally, it is worth mentioning that is always a good idea to read reviews online and in magazines to find out how accurate a programmable thermostat is; how well it performs and other glitches or design errors that users have noticed.
It is hoped that these notes will allow you to choose the best thermostat for you, and that you will make considerable savings to your heating and cooling bills.