During the coldest months of the year the one thing that needs to continuously work without fail is the thermostat – after all, if it’s cold outside the last thing that you want to do is to have the inability to turn the heating up.

Unfortunately for some Nest users that was exactly the problem they faced as a software bug deactivated the system by completely draining the thermostats battery. That means there was no way to turn up the heat or use any other feature of the learning thermostat.

The 4.0 software update that launched in December was found to be at fault, as it caused a battery drain that was far out of the ordinary. Oddly enough however, the bug only became an issue in January and did not seem to affect those who downloaded it in December straight away.

Some people were dealing with the opposite problem however. While the majority of homes were completely without any heating because they had no way to control it, a few were finding that their homes were randomly heating themselves.

“My furnace kicked on at about 5 AM this AM. When I woke up, the house was already at evening temperature,” writes one user on the Nest forum. “An error message came up saying the time was incorrect and something about a battery.”

Despite this problem Nest has issued a short-term fix which involved recharging the thermostat via USB or through performing a nine-step fix, the latter of which hasn’t helped just about everyone.

The company has also pushed through the 4.0.1 software update, despite having earlier claimed that the bugs are not responsible for turning people’s heating off or down. Instead the company accused customers of having incompatible furnaces or forgetting to change air filters for the problem. It also said that hardware issues may have caused it – which if that is the case, is a far more serious issue than a software bug.

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