Green Interior DesignArchives
Which is the Best Programmable Thermostat to Buy?
There is no doubt that most people will save money from installing a programmable thermostat in their home. Even in the US where annual heating and cooling costs are relatively inexpensive because of the cheap price of power, there are significant savings to be made by programming in a 7 day schedule for your heating and cooling requirements. This means that you no longer waste money having the heating on too high at night or cooling an empty house because you don't like to come home to a hot house.
Energy Star have certified a number of different programmable thermostats which makes choosing the right thermostat for your house a hard job. Basically the best programmable thermostats makers on the market in terms of price and performance are made by Honeywell and by Lux. Hunter also make good programmable thermstats.
Honeywell offers a range of programmable thermostats that basically do the same thing. That is why this site promotes the RTH7500D and the RTH8500D. The RTH7500D is cheaper and the RTH8500D has a slicker touch screen interface. Both allow you to program up to four different time periods in a day, compensate for daylight saving hours, have a vacation mode (to give minimal heat/cooling while you are away) and store your programs even during a power outage. Honeywell thermostats (backed by Energy Star) can save you 33% on your annual heating and cooling bills.
The main contender to the Honeywell RTH7500D and RTH8500D is the Lux TX1500E Smart Temp Programmable Thermostat. It costs less than the Honeywell (around $40) and does nearly everything the Honeywells do - lets you set 4 different heating/cooling periods in one day, easy installation to a wide variety of 24-volt heating and cooling systems, saves you 33% on bills and tells you when you need to change the filter on the air-con unit. The difference is that the Lux TX1500E is a 5-1-1 programmable thermostat with only one setting for weekdays. Also it is only compatible with 1 stage heating and 1 stage cooling.
The Lux TX1500E has the added feature of telling you the relative humidity in the room and lets you lock the thermostat with a code to stop kids changing the settings. The main advantage (other than the price) is that the Lux TX1500E gives you control over the swing or temperature differential. This is the number of degrees the thermostat will allow the temperature to rise or fall before the heater or cooler kicks in. This is the only design fault with Honeywells - the swing is a tiny + or - .25. Which means the boiler or cooler can be turned on and off dozens of times in a day. This constant on and off can wear out the HVAC systems. If you live in extremely hot or cold areas the Honeywell might not be for you.
The main complaints about the Lux TX1500E Smart Temp Programmable Thermostat is that the buttons are cheap and stiff and that unlike the Honeywells it doesn't automatically change between heating and cooling systems.
The issue is whether the more exact temperature control of the Honeywell and the better design outweighs the fact that the Lux allows you to adjust swing to better protect your boiler. In temperate weather this is less of a worry.
Read Reviews of the Honeywell RTH7500D | Read Reviews of the Lux TX1500E