Nest And Other Such Thermostats, 2 Wire System - HVAC - DIY Chatroom Home Improvement Forum
Advertisement


Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > HVAC

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread
Display Modes
Old 02-15-2020, 05:46 AM   #1
Newbie
 
Join Date: Feb 2020
Posts: 2
Rewards Points: 4
Default

Nest and other such thermostats, 2 wire system


I have a traditional cold start boiler with a 2 wire system. I do have one internet thermostat, but it's a beast, ethernet cable, big module on the boiler, etc. and a hideous outdated app and website, so I'd like to go wi-fi and put "nest like" tstats throughout (I have 3 zones). I've heard that Nest tstats can "rob" power from the boiler (electricity) for charging its battery, and that this "robbing" can interfere with the firing of the boiler from time to time. I believe my electrician says we can fix this by running a separate "c" or "power" wire, which adds a little to the labor but not too onerous.

Does anyone know of some other alternative "simpler" solutions with other WiFi thermostats?

Thank you!
hotwired99 is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 02-15-2020, 05:57 AM   #2
Hvac Pro
 
yuri's Avatar
 
Join Date: Nov 2008
Location: Winnipeg, Canada
Posts: 22,441
Rewards Points: 188
Default

Re: Nest and other such thermostats, 2 wire system


There are none.

Honeywell ships some of their's with a cheater electronic device which no Pros like. That add a wire device can cause problems with circuit boards. At the end of the day there is no way to cheat or a workaround.

Get the C wire and Nest has a bad reputation also. Go with Honeywell or Emerson/White Rodgers or EcoBee instead.
__________________
"Cut it twice and it is still too short".
yuri is offline   Reply With Quote
The Following User Says Thank You to yuri For This Useful Post:
hotwired99 (02-15-2020)
Sponsored Links
Advertisement
 
Old 02-15-2020, 07:23 AM   #3
Member
 
Join Date: Nov 2014
Posts: 5,840
Rewards Points: 724
Default

Re: Nest and other such thermostats, 2 wire system


Nest is a terrible choice for a thermostat.
You’ll need more conductors in your thermostat wire bundle.
roughneck is online now   Reply With Quote
Sponsored Links
Advertisement
 
Old 02-15-2020, 07:30 AM   #4
Member
 
Join Date: Oct 2017
Posts: 361
Rewards Points: 622
Default

Re: Nest and other such thermostats, 2 wire system


Is there a reason that you need the wifi capabilities? I get it if this is a rental property and you want to spy on what your tenants are setting their heat to, or if you go out of town frequently and want to monitor things to make sure your pipes don't freeze.

Other than those reasons, I think you should quit trying to mess with your thermostat all of the time and just leave it set to one temperature and forget about it. Find a simple heating only thermostat that doesn't require batteries or a "C" wire. The cheaper the better. Don't spend more than about $25 on it.

Boilers take a long time to heat up a space. They work best when they are allowed to coast along at a single house temperature. You won't be saving much money or accomplishing much by programming in a setback.

If your goal is to save money, check into an "outdoor reset" control if you don't have one already. What they do is they tell the boiler to maintain hotter water temperature when it is colder outside, but cooler water when it is more mild. Your house temperature stays the same, but the boiler water varies to be only what is needed.

So as far as a thermostat, I recommend this one.... https://www.amazon.com/CT50K1002-E1-...1772576&sr=8-6

bfrabel is online now   Reply With Quote
Old 02-15-2020, 07:57 AM   #5
Newbie
 
Join Date: Feb 2020
Posts: 2
Rewards Points: 4
Default

Re: Nest and other such thermostats, 2 wire system


Honestly, we only want a wifi tstat housewide because we plan to travel extensively and want to always be able to know in a jiffy what the house temp is, and like, to turn the heat back up when we're on our way home. Right now we have an ethernet wired tstat which is OK, but it's buggy and it's ONLY for the downstairs. So when we travel, we can go on an app and turn it back up to 72 from 60 or 65 but it's only that one zone, so it literally takes nearly 24 hours for our 2K SF colonial to heat up becuase the UPSTAIRS zone is still set for 60. So it would be nice to have that, that's all. Otherwise, what we have honestly is fine. We have decent "hand controlled" thermostats elsewhere and we heat our home almost 100% with woodstove, so again this is just a travel thing.
hotwired99 is offline   Reply With Quote
Old 02-15-2020, 09:25 AM   #6
Member
 
Join Date: Oct 2017
Posts: 361
Rewards Points: 622
Default


Well in that case I'm sorry I yelled at you. You will need the common wire, and then you can pick pretty much any thermostat you want.

As others have said, I would stay away from nest though. The RTH6580WF from Honeywell would probably be a solid choice.
bfrabel is online now   Reply With Quote
Old 02-15-2020, 09:43 AM   #7
Member
 
Join Date: Aug 2011
Location: S.E. Michigan
Posts: 361
Rewards Points: 611
Default

Re: Nest and other such thermostats, 2 wire system


They just covered this problem in a recent Ask This Old House episode: S18 E13: Loose Railing, Smart Thermostat. (It's in the latter part of that episode.)

This is what he used: Invita™ WiFi Thermostat 564

Looked like a pretty neat solution.
More Power! is offline   Reply With Quote
Sponsored Links
Advertisement
 
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Top of Page | View New Posts