Installing NEST Thermostat - two wires

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I just installed 2 of these nest thermostat in my house. Both 2 wire conne ction, un marked, The system is gas, radiant in floor heating and basically if you touch the 2 wires it completes the circuit and you have heat. My n est has a built in battery so it works even when i pull it off the wall. an yways you just need to connect W1 and RH and you are good to go, even if yo u get the wires backwards it will still work, i am not sure on if it will charge the nest if it is backwards. I am going to take a look at my relay box tomorrow and verify the color codes. i have both of the wired opposite so i know they work no matter what.
good luck.
On Saturday, 14 December 2013 07:52:40 UTC-8, Ian wrote:

across the wires.

en or close the circuit.

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snipped-for-privacy@gmail.com wrote:

Nest 'stat has firmware bug, never heard about it? Off topic their smoke detectors are being recalled.
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On Sunday, April 6, 2014 1:39:07 AM UTC-4, Tony Hwang wrote:

ally if you touch the 2 wires it completes the circuit and you have heat. My nest has a built in battery so it works even when i pull it off the wall . anyways you just need to connect W1 and RH and you are good to go, even i f you get the wires backwards it will still work, i am not sure on if it w ill charge the nest if it is backwards. I am going to take a look at my re lay box tomorrow and verify the color codes. i have both of the wired oppo site so i know they work no matter what.

V across the wires.

open or close the circuit.

It apparently has a lot more serious problems. The long list of pissed off customer complaints at Amazon is amazing. Last time I looked, which was months ago, most of the complaints were related to using it in the 2 wire mode, where they try to rob power from the system to power the thermostat. In order to reduce power to make that possible, instead of using small relays like most other thermostats, they used FETs which apparently burn out, don't work, etc. One feature they appear to have that you gotta love is that it can and will install software updates any time it wants to and you have no control over if it does, nor when. Just what you want in a mission critical app. IMO this thing is great if you want a stylish ornament for your wall. If you want a real thermosta t, that works, I'd get a Honeywell VisionPro.
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trader_4 wrote:

I maybe biased as Honeywell retiree, I like Honeywell Vision Pro line my self. Just good for the guy who sold the Nest to Google for 3 billion. Rule is the more a device gets fancy, the more possibility of some thing behaving weird unexpectedly.
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On 04/06/2014 12:31 AM, snipped-for-privacy@gmail.com wrote:

If it charges one way it should charge the other. This is 24V AC so polarity doesn't matter. Phase doesn't matter either since there's nothing to compare it to.

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On Saturday, December 14, 2013 at 7:52:40 AM UTC-8, Ian wrote:

across the wires.

en or close the circuit.

I am considering buying a NEST thermostat today. I have one of the basic tw o wire thermostats where I have a white and a red wire. It's the type with the mercury bulb.
The guy came around from the installers and tried installing a nest three m onths ago and told me it would not work on a two wire system. I have heard different stories about this. Some say yes it does work, other say it won 't work without pulling through a common wire (whatever that is, I am no el ectrician) My two wires are red and white BUT I also have two other wires t hat are there, a black and a green one that weren't connected at the thermo stat. I am wondering if I could use one of those wires as a common if need be. I would imagine they are for a future install of a heat pump.
Can anyone advise me on this?.
Thank you.
On Saturday, December 14, 2013 at 7:52:40 AM UTC-8, Ian wrote:

across the wires.

en or close the circuit.

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On Monday, August 10, 2015 at 11:11:45 AM UTC-4, snipped-for-privacy@gmail.com wrot e:

V across the wires.

open or close the circuit.

th the mercury bulb.

rd different stories about this. Some say yes it does work, other say it w on't work without pulling through a common wire (whatever that is, I am no electrician) My two wires are red and white BUT I also have two other wires that are there, a black and a green one that weren't connected at the ther mostat. I am wondering if I could use one of those wires as a common if ne ed be. I would imagine they are for a future install of a heat pump.

V across the wires.

open or close the circuit.

Assuming those additional wires run all the way back to the furnace, which is likely, then yes one of them could be used as a common to supply power. If the installer was at all competent, he should have been able to deal with that the first time around.
I looked into the Nest a few years ago and from what I saw, there were a huge number of problems, with most of them involving trying to steal power with 2 wire installations. Things like it shorting out, forcing the heat or cooling to full on, regardless of temp.
I think the Nest sucks for other reasons too. Lots of stories of people saying that they can't control it, it just does what it wants, etc. That's how it's marketed, isn't it? I saw people complaining that if they were home from work, sick in bed, and wanted it to just keep a set temp, it would just keep reverting back to figuring out that because it didn't see movement for awhile, it thought you'd left the house..... I don't need that. For me a Honeywell VisionPro that's programmable works just fine. I would get internet connectivity in my next one, so that I could control the heat from my phone, turn it up when I get back to the airport, etc. Could get a VP that does that for $150.
Also, don't be fooled into some incredible claimed energy savings. Those savings are mostly due to what you can do with any programmable thermostat.
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In alt.home.repair, on Mon, 10 Aug 2015 08:19:51 -0700 (PDT), trader_4

This is the wave of the future. If you're just going to lie in bed for hours, you should have gone to a hotel.

Of course you don't NEED it but it's modern, high-tech, and it's what we will all have soon.

There's something about coming into a cold house that seems like part of taking a trip. It doesn't take long to warm up.

I'm sure you're right.
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micky wrote:

under-rated relay causing a/c compressor burn out when relay sticks. There are many other choices like Ecobee, 3M, Honeywell, etc. They are all WiFi thermostats. I believe 3M one is made by Honeywell.
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Tony Hwang wrote:

Honeywell thermostat. I can control it any where in the world using internet. using computer or smart phone)
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In alt.home.repair, on Mon, 10 Aug 2015 22:23:28 -0600, Tony Hwang

Of course that means terrorist hackers can turn up the heat in your house. You've been warned.
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micky wrote:

cause freezing or over heating due to AI.
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On 08/10/2015 11:40 PM, micky wrote:
[snip]

That's one reason I want a thermostat I control.
BTW, At this moment I happen to be looking at my network router. It's one computerized thing I can connect to directly to change it's settings. No company has access.
--
Mark Lloyd
http://notstupid.us/
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On 08/10/2015 11:23 PM, Tony Hwang wrote:
[snip]

When you do so, are you connecting directly to the thermostat or to a web server that's controlled by the company? If the latter, then someone else actually has control over your thermostat in a way that you don't.
It shouldn't be too expensive for a thermostat to contain an embedded web server, and then YOU connect to IT. I find this very important.
--
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http://notstupid.us/
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Mark Lloyd wrote:

access. Nothing in the world is 100%, perfect;y secure. Ever heard of any system scoring perfect security ratings according to mil-spec.? When I was retiring best there was B2 rating. My home network is UTM enterprise class router based, best I could afford. So far never been compromised by hackers. Any way if there is unauthorized intrusion, at least I'll know any way as soon as it happens. BTW, I use wired gateway for outside connection. At least one less worry not using WiFi method.
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In alt.home.repair, on Tue, 11 Aug 2015 11:02:41 -0600, Tony Hwang

No, it's not.

There's perfect, there's almost perfect, and there's far less than perfect.

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On 8/10/2015 9:11 PM, micky wrote:

You need three wires for heat only, common, 24VAC, and RH (request heat). It's good to have more wires, one for fan-only, and one for RC (request cool). It would be surprising if the extra two wires you have don't run back to where the furnace is.
You do not want to install a NEST thermostat in "power stealing" mode because it can destroy the furnace's controller board.
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On 08/10/2015 11:33 PM, sms wrote:
[snip]

The new system I got a couple of years ago requires 7 wires, since it has 2-stage heating and cooling (not heat pump). They actually put in 10 wires (3 available for future use).
[snip]
--
Mark Lloyd
http://notstupid.us/
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Mark Lloyd wrote:

is so handy.
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"micky" wrote in message

Miky: what you have it is just Heat Tst. you need to look for two wire type Tst. Two wire can be use also for heat but it require sub control to switch from heat to cool or wisa wersa More sophisticated Tst. would not work for you as is, it must have backup battery. but yes it can still be hooked up to do the job however person must know what it is doing.

This is the wave of the future. If you're just going to lie in bed for hours, you should have gone to a hotel.

Of course you don't NEED it but it's modern, high-tech, and it's what we will all have soon.

There's something about coming into a cold house that seems like part of taking a trip. It doesn't take long to warm up.

I'm sure you're right.
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