Nest has changed its Thermostat for the UK to cope with different heating systems.
Nest is finally selling its Thermostat in the UK. Centre is the main unit, on its left is the new 'Heat Link' and an iPhone running the Nest app.
For £29 ($50), you can buy a stand that lets you plug the Thermostat in anywhere, removing the need to wire it in to a wall.
The Heat Link box needs to be wired into a boiler, replacing the existing programmer.
The Thermostat sends commands to the Heat Link box wirelessly, telling the boiler when to turn off and on.
You can use an iPhone or Android app to change the temperature of your house.
The app gives you information about your energy usage, showing the temperature at various times and when the auto-away feature activated.
The sensors in the Thermostat measure temperature and humidity, amongst other things.
The Thermostat works with the Nest Protect. The app reassures you that there's no fire or deadly carbon monoxide.
Turn the temperature down and you will see a green leaf on the screen that lets you know you're saving energy.
Help messages appear on the screen to help you use the Thermostat.
The Thermostat knows how long it takes your heating system to warm your house and adjusts the turn-on and shut-off times accordingly.
You can make sure that the auto-away feature that turns your boiler off when everyone leaves the house is enabled here.
Turn the dial and push the screen inwards to select the menus options at the edge of the screen.
You can manually set the boiler schedule if you wish.
When you increase the target temperature, the Thermostat tells you how long it will take your heating system to reach it.
You can change the readout to show Fahrenheit or Celsius.
The UK Nest Thermostat is on sale today for £249 ($420) including installation.
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