.Spoiler – it wasn’t a capacitor.

If attempting a repair like this then take extra care to ensure the power is off to the PCB. It has a lot of exposed live tracks on it.

Do you remember when thermostats were cheap, simple and lasted for over 30 years? Welcome to the future where they are expensive, crammed with electronics and may not last a tenth of that.

I think this one managed to scrape by its one year warranty period before ceasing to sense.

I would categorise my test-bodge as a temporary measure to identify the fault. It would be better to get the proper component, although it’s not an easy one to desolder. It may require more aggressive heat pen use and probably some careful masking with Kapton tape to protect adjacent components.

In use the unit seems to run pretty cool. The two hottest components visible to the thermal camera were the PSU diode and the PSU primary side MOSFET, and neither of them was particularly hot.

The Nest Thermostat revolutionized the way that people control the climate in their homes. It has features more features than even the best programmable thermostats. But, all of the premium features also come at a premium price. On the other hand, for only $5, a little coding, and the realization that thermostats are glorified switches, you can easily have your own thermostat that can do everything a Nest can do.

[Mat’s] solution uses a Sonoff WiFi switch that he ties directly into the thermostat’s control wiring. That’s really the easy part, since most thermostats have a ground or common wire, a signal wire, and a power wire. The real interesting work for this build is in setting up the WiFi interface and doing the backend programming

NEST your old thermostat under $5
https://notenoughtech.com/featured/nest-your-old-thermostat-under-5/

Alphabet’s Nest Working on Cheaper Thermostat, Home Security System
https://www.bloomberg.com/news/articles/2017-03-08/alphabet-s-nest-working-on-cheaper-thermostat-home-security-system

Nest, the pioneer of the iPhone-like digital thermostat, is readying several new products in its quest to modernize the home.

Alphabet Inc.’s Nest, seeking a bigger share of the connected home market, is developing a cheaper version of its flagship thermostat and new home security products, according to a person familiar with the matter.

The company is working on a version of its “learning thermostat,” which adjusts the temperature based on usage patterns, that would sell for under $200, the person said. The current version sells for $249. The cheaper model would include less expensive components and at least one internal prototype lacks the flagship model’s metal edges, the person said.

A home-security alarm system, a digital doorbell and an updated indoor security camera are also in the works, representing potential good news for a company that has struggled to release many new products.

Nest’s time at Alphabet: A “virtually unlimited budget” with no results
Nest quadrupled its employees, launched no new products, and caused constant bad PR.
http://arstechnica.com/gadgets/2016/06/nests-time-at-alphabet-a-virtually-unlimited-budget-with-no-results/

Nest CEO Tony Fadell wasn’t officially “fired” from Nest, but it certainly feels like it. Nest and Alphabet announced Fadell would be “transitioning” to an advisory role at Alphabet, dropping both Nest and Fadell into a sea of negative press.

When Google bought Nest in January 2014, the expectation was that a big infusion of Google’s resources and money would supercharge Nest. Nest grew from 280 employees around the time of the Google acquisition to 1200 employees today. In Nest’s first year as “a Google company,” it used Google’s resources to acquire webcam maker Dropcam for $555 million, and it paid an unknown amount for the smart home hub company Revolv.

In return for all this investment, Nest delivered very little. The Nest Learning Thermostat and Nest Protect smoke detector both existed before the Google acquisition, and both received minor upgrades under Google’s (and later Alphabet’s) wing. A year after buying Dropcam, Nest released the Nest Cam, which was basically a rebranded Dropcam. Two-and-a-half years under Google/Alphabet, a quadrupling of the employee headcount, and half-a-billion dollars in acquisitions yielded minor yearly updates and a rebranded device. That’s all.

Too slow for Google

Actually delivering a product to market is Nest’s biggest problem. Dive into reports about Nest and you’ll see those 1200 employees were busy with countless products that never got out the door.

Flintstone seems like another case of Nest being too slow for Google. The Information report says that Google’s OnHub router “performs some of the functions that Nest’s Flintstone was at one time meant to perform.” Google even included a dormant Thread radio in the device. Rather than wait for Nest, it seems Google went out on its own.

Then there are all the Dropcam projects Nest inherited and never turned into anything

Performance of the existing products is an issue too.

Google and multinational manufacturer Honeywell have resolved their long-running patent dispute over the thermostats produced by Nest Labs, the two companies announced today. Honeywell first filed a patent infringement suit against Nest’s Learning Thermostat in early 2012, two years before the home automation company was purchased by Google. There are no details on what the settlement entails, but the two companies said they now shared a “long-term patent cross-license agreement reflecting the respective strength of the companies’ patent portfolios.”

After a spate of damning articles about Nest, CEO Tony Fadell came to the weekly staff meeting of sister company Google to counter the negative press and defend Nest’s corporate culture and sales figures.

Nest is the smart-home device subsidiary under Alphabet, the parent company of Google, which bought Nest for $3.2 billion in 2014. Late last month, some of Nest’s struggles surfaced in a series of reports.

The first, a lengthy article in The Information, detailed a corrosive internal culture after Nest’s acquisition of Dropcam, which makes connected video cameras. Dropcam’s founder, Greg Duffy fired back in a Medium post further attacking Fadell’s management style and said he regretted selling his startup. On March 30, Re/code reported that Nest’s sales figures for 2015 — around $340 million — fell short of the initial targets set by Google at acquisition.

Remember Nest Labs? Google spunked $2bn (£1.41bn) on the home appliance outfit two years ago.

The acquisition was supposed to put Google-owner Alphabet at the heart of the “internet of things,” and in the consumer mainstream. Nest cofounder Tony Fadell had been the design force behind the iPod as a contractor. Google mostly innovates through acquisitions rather than its own in-house R&D.

But, other than the odd reiteration, Nest hasn’t released a new product since 2013.

puts the blame on egos – Fadell’s, principally – and also the bean counters within Alphabet. Nest’s last product was a rebadged camera, the result of a $555m acquisition of Dropcam.

Four new Nest products are in the offing, including Bluetooth key fobs and a low-power wireless hub codenamed “Flintstone,” The Information also reveals. The trouble is, everyone else is making these too: Huawei and Samsung have comprehensive “connected home” products stacks. Even Amazon is miles ahead.

A thermostat is a component which senses the temperature of a system so that the system’s temperature is maintained near a desired setpoint. The thermostat does this by switching heating or cooling devices on or off.

Since I wanted to test the concept of how it would be like to build a thermostat, I created a prototype.

The system is controlled by a Particle Photon or Core dev kit. Since it needs to know the temperature, a DHT22 is required. Also, to control the HVAC system I have at home, I used 5 volts relays.

This project will be messing around with an expensive system, my HVAC. When the time comes for the installation I want to be sure that nothing goes wrong, or at least minimize my chances of something going bad.

For this I have created a visual feedback system that I will use as my HVAC simulator. It’s made of Lego and pretty basic, so bear with me

The Finite State Machine library

Soon I discovered that there were no FSM libraries for the particle, but when searching a library for Arduino, I found this one. I tried it and it was an excellent fit for me.

With the permission of the original author, I ported and published it in the particle libraries for everybody’s benefit.

http://playground.arduino.cc/Code/FiniteStateMachine

Owners of the Nest thermostat have been unable to heat their home after bug in the internet-connected controller forced it to shut down.

The company, bought by Google for $3.2 billion (£2.2 billion) two years ago, admitted that that a software update had gone wrong, forcing the thermostat’s batteries to drain and rendering it incapable of controlling temperature.

It left users of the £200 “smart” device, which is designed to save energy by learning what temperatures owners like and when they are away, with cold houses and fears of burst water pipes.

“Woke up to a dead Nest and a very cold house. Not good when you have a baby sleeping!” one user wrote on the Nest internet forums.

The thermostat connects to the internets and smartphones, allowing users to control central heating and hot water remotely, as well as programming itself to save energy.

Sales of Nest and other “smart home” products are growing rapidly, but some experts have feared that connection failures and cyber-attacks could disable or compromise these devices.

Nest urged owners to follow a nine-point guide to reset their thermostats, including recharging and resetting it, and said it was preparing a solution.

“We are aware of a software bug impacting some Nest Thermostat owners,” a spokesman said.

“In some cases, this may cause the device to respond slowly or become unresponsive.”

What to do if your Nest Thermostat has become slow, unresponsive, or won’t turn on
https://nest.com/support/article/What-to-do-if-your-Nest-Thermostat-has-become-slow-unresponsive-or-won-t-turn-on

Some Nest Thermostats that have been updated to software version 5.1.3 or later may become unresponsive or may not charge the battery efficiently, causing it to shut down. Recharge and restart your thermostat to get it working again.