Gen 1 NEST Low Battery

[TheHueg]

This morning I noticed my Gen 1 NEST Learning thermostat would not light up when I walked by.    I tapped it and it came on indicating BAT Low.    It also referred to low or no power.    I've never seen this before.    Although the house temp was well below the COOLING set temp, the unit was still running.   I presume it was confused as the WI-FI was off (due to low power).     So, I charged up the batteries with a cord.    After two hours I plugged the face onto the base and everything is working fine.    The readings are:   Battery -3.909 V; Voc-37.84 V; Vin-33.83 V; and lin-100mA (c).    Are these readings "normal"?   Why did the battery get low and no power after 6 years of working just fine.    Why is it now apparently OK?

[aperezdeleon]

Hello TheHueg,

Thanks for reaching out to our community.

Sometimes the Nest Learning thermostat battery's behavior can be confusing. Let's break down what might've caused the thermostat to lose power.

The readings on your thermostat are okay, indicating it's receiving enough power for the battery to stay charged and the thermostat to function as expected.

One reason your thermostat's battery might be low is difficulty connecting to the internet. If the thermostat is constantly trying to connect, the battery will drain faster. Interference causing frequent internet disconnections could be the culprit.

It's also important to ensure your system has been properly maintained. Various factors could cause power loss in your system, so monitor the power readouts if the battery drains again to determine if the power could be the reason why this is happening.

Let me know how it goes.

Regards,
Angel.