NY Times article on Nest and IoT generally

(Shelley Powers) #1

Good NY Times article about Nest and the buggy software update for their thermostat.


I was one of the folks impacted by the Nest breakdown


Nest only responded in the thread about the issue yesterday. I replied it was too late: we were all frozen to death.

SmartThings can annoy the heck out of me at times, but it responds quickly to issues. And that’s why I stick with it.

(Marc) #2

I installed a new HVAC system yesterday and my Nest is now reporting my “G” (fan) wire doesn’t have enough power. It’s not preventing my A/C from working since my air handler normally powers the fan, but it does prevent the Nest from turning on the fan independently. I was shocked that a brand new install like this had this issue. I called Nest support and they were great and explained the situation as most likely not a big deal but to check with my HVAC installer as it could be an indication of a problem. Nest support had me measure the voltage of the line through the software which came out to 6 volts but 24 is required. Anyway, my HVAC installer is going to come and check it out, but I am curious if others have had similar experiences?

(Shelley Powers) #3

No, we didn’t have that problem. We can run the fan independently. In fact, I have an IFTTT recipe that turns on my fan when my indoor Netatmo weather stations detect carbon dioxide over 1500 ppm.

The only time I’ve had issues is dropped wireless, before I bought the OnHub router from Google. The Nest thermostat seems to like it much better than my older router. The only other problem I’ve had is the one everyone had with software version 5.1.3, draining the battery. I just noticed my version is now 5.1.6, so they upgraded in last few days (checked, yup, on January 11). It will, hopefully fix the awful bug that killed my thermostat.

The issue with the battery is not having a C wire, nothing to do with G wire. You’re not using an add-a-wire are you? I believe this works with the G wire.

Anyway, sounds like having the HVAC person out is best option.

(Shelley Powers) #4

Did want to note that if you do have thermostat, and it goes dead, plugging it into computer usb port about 10 minutes will help get it jump started, and you can fully charge it in about one hour.

Also, and double-check with your HVAC person on this, crossing the white wire (heat) with the red (power) will turn on the heater. In an emergency.

(Marc) #5

Yes, unfortunately I have charged my Nest many times via mini-usb. My heating and cooling power wires are fine, it’s the fan that’s the issue.

(Shelley Powers) #6

I’ve only had to do it once. I’ll see what happens during down times again this Spring.

Hope fan gets resolved. Curious, too. If you can post a follow-up after the HVAC guy is by, would appreciate it.

(Marc) #7

Sure. His response via text was “Your A/C turns on your fan, so you will be ok”, which he is right about. Having the green/power wire connected is really only needed if you want to control your fan from your nest separately, which I never do, but still want this issue fixed. My other central air unit (I have 2) I have this ability. I found it strange on a brand new install that I am having this issue.

(ActionTiles.com co-founder Terry @ActionTiles; GitHub: @cosmicpuppy) #8

Sorry, what? I guess it is all relative, but there are a heck of a lot of issues that SmartThings has not responded to, or that took, literally, months to resolve (or not been resolved yet, ever).

(Bobby) #9

I totally agree :wink: :wink:

(Shelley Powers) #10

They don’t always have all the answers, but consider this:

I had an issue with Netatmo and emailed support December 15th. I’m still waiting for some response.

Nest took over a week to respond to a forum thread about dead thermostats–something that is not trivial.

I won’t even get into trying to get help from Google about OnHub. shudder

ST does respond. Maybe the only response is, “We’re aware of it, we’re looking for solutions”, but at least you know you’re not shouting out into the void. That matters.

As long as ST keeps listening to their customers, I’ll continue to be a customer. An annoyed one at times, but still a customer.

(Paul) #11

In a new install, you should have enough wires to run a dedicated C. That will power the thermostat. Even tho a Nest can run without a C wire, trust me, you will have many fewer issues if you have one. When the installer comes back, have him hook up the thermostat with a C wire. You’ll have better WiFi connectivity, and your battery will never die.

If you’re only getting 6V on G, there’s definitely a problem somewhere in your system.

And finally, you do want the Nest to be able to control your fan. The AirWave feature on the Nest (runs the fan after the cooling cycle finishes under certain temp/humidity conditions) saved me a bundle the last few summers.

(Marc) #13

Thanks and good info about the airwave. My other ac unit probably took advantage of that. Unfortunately running the wires from the air handler in the attic to the thermostat two flights down was s big challenge and now all my walls are all sheet rocked up and painted. I don’t think running a C wire is an option. I’m mad at myself for not asking for this ahead of time.(going through a major renovation and many things on my mind) I just hope the green fan power wire is not damaged…

(Paul) #14

Thermostat wire these days usually has 8 conductors at least. Are you sure there aren’t more conductors in the wall?

There are a few ways to get 24V to your thermostat. When the contractor comes back he can give you some solutions I’m sure.

(Shelley Powers) #15

You don’t need a dedicated C wire. You can also use the add-a-wire solution, as noted in the Hack Your Home article listed in original topic posting.


But I didn’t think that was your problem. Your problem was the G wire for the fan. I had forgotten about air wave, and that is nice. But still, running the fan automatically when rooms get stuffy has been the bigger winner for us.

(Shelley Powers) #16

And if you do use the Venstar, definitely need the installation video

(Marc) #17

These are the wires I have hooked up. It detects my fan wire but complains it lacks power. Nest support had me swap the G and Y and then I read them the power readings and that is how we determined I only have 6 volts coming from my fan wire.

Another thing to note…this is my downstairs and it’s very cool down there to begin with so humidity is usually not an issue. I would still love to get this fixed though.

(Paul) #18

There aren’t any more conductors in the cable? Maybe pushed back into the wall somewhere? Like I said, most cable they use these days has more conductors than you are currently using.

Also confirm with your installer that you need both Rh and Rc (meaning you have a dual-transformer system). You might be able to repurpose Rc.

But step 1 is figuring out why you only have 6V on G.

Good luck and let us know how it goes!

(Marc) #19

Thanks. I am going to wait until it gets warmer so we can fully test the ac. We are in the dead of winter here in the Northeast, even though it was mid 50’s today!

My RH was from my original radiator heating system. That was originally part of the house and I just added central air to the zone.

(Paul) #20

That all makes perfect sense.

(Marc) #21

Thanks @NorCalLights for your help again. I finally had my HVAC guy out today and Nest was spot on, my G wire was frayed behind wall and he fixed it. He didn’t believe Nest at first and went out to Home Depot and bought another thermostat which didn’t work either. Props to Nest support and their device for pinpointing the exact issue, something an older thermostat could not do easily.