I’m a huge proponent of new technology. I love it when companies create new technology to solve problems. I appreciate it when old technology is re-imagined, using the best of what’s available to take old technology to a whole new level. When all of this is accomplished at the same time I almost start drooling uncontrollably. It gives me that feeling that I’m living in the future.
So it’s pretty understandable to those who know me that I was a wee bit on the excited side when I was first introduced to the idea of the Nest learning thermostat, from Nest Labs (now owned by Google). They took the old mercury thermostat and transformed it into a masterpiece of modern technology. A thermostat that learns from you, knows when you’re home and when you’re not, and automatically creates a schedule to heat and cool your home to maintain your comfort level so that you don’t have to ever even think about it again. On top of that, it sports a user interface and aesthetic appeal that is absent from every other thermostat on the market (at the time – I don’t know if other t-stat manufacturers have corrected that, but I’ve not heard of any). I was blown away! I had to have one (two, actually…).
And so I got them. I pre-ordered and when the time came I was giddy with anticipation. Over a thermostat. Never in a thousand years would I have thought I would be giddy at the idea of getting my hands on a thermostat.
Wiring the thermostats went well – both reported “seeing” all of the wires correctly and everything seemed to work. Later I noted that one of my air conditioner condenser units was running even when neither of the Nests was calling for AC. After talking with Nest support, they determined that it was because the Common wire I had attached wasn’t apparently working correctly. The nest was defaulting to “power stealing” mode, which caused the zone panel to activate the air conditioner. Their solution ultimately was to disconnect the common wire, as they said I didn’t need it, and bypass the zone panel. I did so, intending to get to the bottom of the wiring issue. It worked ok. I got busy and forgot entirely about trying to nail down the weird wiring issue.
Flash forward to December 2013. While gone for Christmas, the Nest that didn’t have a common wire ran it’s battery down due to a wifi issue, and dropped off the network. A massive cold front moved through while we were gone and I wasn’t able to adjust the temperatures remotely (one of the big draws to the thermostat). I also wasn’t entirely sure the thing hadn’t just gone completely offline leaving me without anything to tell the furnace to power up and heat. Knowing that typically when something like that happens it can be solved / prevented by having a common wire attached (to give it a full 24vac circuit to power itself and recharge it’s battery without stealing from the other wires). I decided I needed to get to the bottom of the wiring issue so I could avoid having this happen again.
The first order of business was to check the current wiring to try and diagnose the issue. Using a voltmeter I was able to determine that the wiring was actually fine. The R (power) wire and the C (Common) wire (red and blue respectively in my system) are hooked to the two sides of the transformer in the furnace. When your thermostat goes to say, turn on heat, it will close a connection between R and W (heat) – providing power to the furnace, which then complete the connection back to the common side of the transformer to close the 24vac circuit completely. Many modern thermostats rely on the C (common) connection so they can complete the circuit and use that to power the thermostats advanced functionality. This means that when you use a voltmeter and test between R and C, you should see 24vac registered. So I did just that… and saw the expected 24vac.
A call to Nest Support ended with them telling me that it was definitely the wiring, and that it’s because “your common wire isn’t grounded right so your power is just going out and being lost”. I called bullshit, but the guy was persistent and it was clear I was going to get nowhere.
I opted for a test to give me more weight behind my claims when I called back. I removed the nest (including base) that was working flawlessly downstairs, and replaced the problematic nest with it. Sure enough, it worked flawlessly. It detected the wiring without issue – including seeing correct voltages and power. It powered the furnace without issue. It just worked.
A second call to nest support – relaying this new information – resulted in them agreeing to overnight me a replacement 1st gen unit, as they thought it was the base plate that was having the problem.
After a week the replacement finally arrived (yes, a week – that’s a separate issue entirely, the short version being that their support engineer failed to put a valid address on the shipment. It just had a street name and city. The street name was spelled wrong – after I had spelled it out for him twice.) I put it in place and all seemed ok. It detected the wiring fine.
Last night I pulled this replacement off the wall and put a Honeywell back in it’s place. The Nest would report to me that it was calling for heat, but our furnace would sit idle, it’s status light blinking a slow, lazy blink indicating that it’s just hanging around waiting to be told it’s needed. Meanwhile the temperatures upstairs would drop farther and farther away from the set point as the temperatures outside plummeted (again). No “tricks” worked to get it to actually call for heat. I tried all of the things I could find on the Nest forum for this kind of scenario.
I moved the set point below the current temp and back up. Nothing.
I turned the heat off for a few minutes (10+) and back on to see if it would reset itself. No dice.
I pulled the unit off the base and put it back on, and waited the 3 minute countdown before it would attempt to call for heat. Nope.
Desperate for a solution I attempted a factory defaults reset thinking that for sure this had to fix it. It did not.
That was the last straw. I found an old Honeywell thermostat and quickly hooked it up in place of the Nest. Not long after hooking it up (it has to go through a wait period before it will call for heat) I heard the glorious sounds of the long slumbering furnace rumble to life, followed soon by warm air blowing sweetly from the registers. Any doubts as to the culprit of the problem vanished – the Nest had failed me. Again.
And at that moment I felt a little deflated as a geek and technologist. For, as much as I love to see modernity brought to old technology, I know it’s ultimately pointless if the resulting product is not as stable and reliable as the old technology it’s meant to replace.
Mercury dial thermostats were very basic, but did their job exceptionally well. Aside from having to set the temperature you want them to keep manually, you pretty much forget they’re there and don’t worry about whether or not they’re going to work. They just DO.
I’ve lost faith in Nest, and their ability to deliver a product that I can trust. I don’t give a whit about any of the features, the aesthetic, the user interface or ability to access it remotely if it cannot be trusted to perform the basic function that is ultimately it’s SOLE PURPOSE for existing.
I’m sad that it’s gotten to this point. I used to recommend Nest to anyone who would listen. Now I can’t do that. I apologize to everyone I’ve recommended Nest to, especially if you’ve had an issue with yours.
(authors note: As of the time of writing, an email in to Nest support has gone unanswered. @NestSupport did respond via Twitter when I commented on my problem, but have not followed up since reaching out for – and receiving – more information.)