• Paul Fingleton

How Installing a Nest Thermostat Ended Up Costing Me Over €10,000 [Part 1]

Back in December we reported that the Nest Learning Thermostat was available throughout Ireland and took the opportunity ourselves to organise a free Nest and take it for a test run.


Providing a detailed review or test of something like a Learning Thermostat isn't something that can effectively be done in a week or two - the device has to learn your habits, your preferences and then adjust to what you like.

While we expected the Nest to make in impact relatively quickly in our home, we didn't get the results we were expecting.

For the first week the Nest was reporting that it had the heat on for 12 to 14 hours a day, and that a small change in heat settings would take 2+ hours to reach the desired temperature.

All the documentation said that it takes time for your Nest to get to know your schedule and the temperatures you like and adjust the schedule accordingly. So, we sat back and held our nerve. The Nest would learn our schedule, learn when we're not at home and switch off the heat. It would learn how long it would take to get up to a temperature and switch on the heat just for that right amount of time. Then the energy savings would kick in.

Sure enough, the thermostat popped up with a message after a week to say that it now had enough information to enable the Auto-Schedule function. But any change of temperature still took several hours and the usage showed that the heat was on for more than half a day, every day.

Our first monthly Nest Energy usage report came in at a staggering 243 hours, or an average of 9 hours for every day we had the Nest in December


In January, we tried to adjust the schedule to manually control the temperature more, negating much of the auto management features of the Nest but hoping to save some money.

We tried rebooting and resetting the Nest, we even changed out our home Wireless Router because the Nest seemed to be frequently dropping off the network and going offline.

Each day still showed high energy usage, but at least we were controlling it ourselves a bit more. Then our January energy report arrived: 264 hours, or 8.5 hours average per day.


This was getting ridiculous, having the heating burning for over 500 hours for just two months and not feeling the benefit in terms of heating was ridiculous.

There had to be something wrong with the unit. The Nest must be faulty, or just a marketing ploy, or maybe there was something else at play here. A reason why the heat was burning for hours, but the house was still cold?

Surely there was something wrong. Or could everyone really just have investment bias after spending a few hundred euro or dollars on a thermostat: Could it be that they just didn't want to admit they had bought a turkey?


How did we end up spending over €10k because of Nest? Read on in Part 2 next week.