I moved five months agao and had not installed the nest yet. When I hooked it up it only showed
a red blinking light
On top of the unit. It turned out that the device needed to get charged via the mini USB adapter in the back. After about 5 minutes, a small dull nest home screen showed up.
After maybe another minute the screen said:
Please attach display to its base
It turns out that this message tends to be over optimistic: After connecting the device
it fell back into the red-blink slumber.
I gave the device 10 more minutes of USB charge. I used an actual physical charger, not a USB connection from a computer. The ampere that the unit sees can be quiet different.
A drained rechargeable battery certainly appreciates the flow a nice and solid current.
After said 10 minute charge things got better: the thermostat started ‘boot’ while being connected and it was able to operate the heat pump. At this point it still said
in the Wifi and other connection related screens. Since this did not change for an hour I gave the display another 30 minutes on the USB charger and then was able to set up the network connection as expected.