The Nest Thermostat is a smart thermostat developed by Google Nest and designed by Tony Fadell, Ben Filson, and Fred Bould. It is an electronic, programmable, and self-learning Wi-Fi-enabled thermostat that optimizes heating and cooling of homes and businesses to conserve energy.
The Google Nest Learning Thermostat is based on a machine learning algorithm: for the first weeks users have to regulate the thermostat in order to provide the reference data set. The thermostat can then learn people's schedule, at which temperature they are used to and when. Using built-in sensors and phones' locations, it can shift into energy-saving mode when it realizes nobody is at home.
Specifications, North American versions
Note: Generation E and new thermostat supports two stage cooling OR two stage heating OR heatpump due to a shared multi-use terminal.
Hardware
Nest is compatible with most standard HVAC systems that use central heating and cooling and uses industry standard connections to facilitate the control of these appliances.
Nest is not compatible with communicating HVAC systems. Communicating systems are used with some two-stage and all variable-capacity HVAC systems. These systems require just four wires – two power wires for heating and cooling and two for communication between components (see photo).
Nest consists of two primary pieces of hardware. The display contains the main printed circuit board (PCB) and rotating ring (except for the 2020 Nest Thermostat, which has a touch-sensitive strip on the right side of the thermostat body). The base houses the connection terminals, bubble level, and holes for wall anchors. Neither can function independently; if separated, the display becomes inactive until reconnected to the base.
A special version of Nest is available in Europe, which is capable of controlling 230 volt heating systems. The Nest is paired with a "Heat Link" device, which contains the circuitry required for controlling the mains-voltage heating system. The first release was the 2nd Generation Nest thermostat which the Heat Link controlled the central heating boiler. The 3rd Generation added support for OpenTherm and for controlling domestic hot water. The Nest E was made available to the UK in October 2018. It has several major changes as the thermostat is stand mounted only, the Heat Link is grey and battery powered, the Heat Link loses the domestic hot water support, and lastly designed to be installed on the wall where the old thermostat was located.
As the Nest Thermostat cannot be battery operated, it must either be installed with a wire connecting directly to the "Heatlink" which supplies 12v DC, or mounted on a Stand and powered via a USB cable.
The Nest Temperature Sensor was added in March 2018. Available in Google Store only for United States and Canada. Up to six of these battery operated devices can be added to a single thermostat to provide remote temperature monitoring. Nest will then use the appropriate sensor based on schedule. Since they use Bluetooth Low Energy they are only compatible with the E and 3rd generation thermostats.
With the introduction of the more accessible Google Nest Thermostat on October 12, 2020, it no longer features the rotating ring which is present on other Nest models. It instead uses a touch-sensitive strip on the right side of the thermostat body to adjust temperatures and navigate the thermostat's operating system, with tapping on the touch-sensitive strip replacing physical clicking. It also features presence detection which uses Google ATAP's 60 GHz Project Soli radar, which allows the mirror-like face of the Nest Thermostat to have no visible cutouts for the radar sensor. This enables the thermostat to display the current HVAC status when human presence is detected by the Soli radar sensor. However, Nest Farsight is not supported on this model but poses a similar function at closer distances.