Smart thermostat issue - do I redo the wiring or add a transformer?

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imyeti2
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Smart thermostat issue - do I redo the wiring or add a transformer?

Post by imyeti2 » Fri Sep 14, 2018 5:31 pm

Hello,
We have an old honeywell round thermostat for heating only. It has the standard 2 wire thermostat wire. From all I've seen, for us to upgrade to a smart thermostat, I need the dreaded C wire.
I asked several electricians about options. I have always thought that I need to change to new wiring for the thermostats to work. One option suggested is to add transformers (I have 5 heat zones) near the thermostats. Cost may be $300-500 less than full wiring. Full wiring is ~$1200.
Is it worthwhile to invest in this transformer solution or to just upgrade the wiring. My inclination to upgrade the full wiring is then to future proof the home - if I change the boiler in the future, I hope to have the most up to date wiring.
However, the transformer option is cheaper and easier solution.
Any thoughts? Thank you.

runner3081
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Re: Smart thermostat issue - do I redo the wiring or add a transformer?

Post by runner3081 » Fri Sep 14, 2018 7:25 pm

I would really explore the value of a "smart" thermostat. We have been using one for about a year and honestly, I could live without it.

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Toons
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Re: Smart thermostat issue - do I redo the wiring or add a transformer?

Post by Toons » Fri Sep 14, 2018 7:47 pm

"One does not accumulate but eliminate. It is not daily increase but daily decrease. The height of cultivation always runs to simplicity" –Bruce Lee

dknightd
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Re: Smart thermostat issue - do I redo the wiring or add a transformer?

Post by dknightd » Fri Sep 14, 2018 7:56 pm

You said you had 5 zones. Do they each have a separate thermostat?

eddot98
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Re: Smart thermostat issue - do I redo the wiring or add a transformer?

Post by eddot98 » Fri Sep 14, 2018 10:21 pm

1. I had the same situation, needing the C wire, but we only have one zone and one thermostat. I hired an electrician to install the thermostat and instead of running a C wire all the way to the boiler as I thought was necessary, he just tapped into a doorbell circuit that was just below the thermostat in the basement for power. Case closed, one hour of labor in total, including installing the thermostat and making sure that it worked correctly. He did a few other small jobs for us that day.
2. We find great value in our smart thermostat. We really only have one use for it: to turn up the heat before we return home from being gone a few days or more in the winter (we live in New England). Returning to a warm house is a real luxury. We don’t have central air conditioning, so we use smart plugs to turn on our window air conditioners before we return home in warmer weather.

wilked
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Re: Smart thermostat issue - do I redo the wiring or add a transformer?

Post by wilked » Sat Sep 15, 2018 6:08 am

I have two wires and a smart thermostat

Emerson Sensi Wi-Fi Thermostat for Smart Home, ST55, DIY Version, Works with Alexa https://www.amazon.com/dp/B01NB1OB0I/re ... NBbC32F4KS

Love it, works great

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Bammerman
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Re: Smart thermostat issue - do I redo the wiring or add a transformer?

Post by Bammerman » Sat Sep 15, 2018 7:35 am

Similar situation, except that I had only one old round Honeywell thermostat (i.e., one "zone"). I solved the situation by buying a $20 programmable thermostat (uses AA batteries that last at least a year). It is only smart enough to change the set temperature several times a day 7 days a week, but that's smart enough for my boiler/steam radiators, because they are too slow to respond to frequent change orders coming from anything "smarter". Is your heating system/furnace capable of utilizing a smart thermostat?

imyeti2
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Re: Smart thermostat issue - do I redo the wiring or add a transformer?

Post by imyeti2 » Sat Sep 15, 2018 7:49 am

Thank you for the responses and for sharing your stories.

We have 5 heat zones and 1 cool zone. One of the heat zone is a combination with the AC. Three zones are controlled on the 1st floor, the other two on 2nd floor along with the AC.

During winter, before going to bed, I've to manually check all zone and dial down the temperature on the 1st floor. Most of the time we do it - sometimes we forget.

We live in New England. This past brutal winter, we're away last December and were worried about things working well etc. My preference for a smart thermostat was to be able to check everything remotely and make changes as necessary.

Sportswhiz00
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Re: Smart thermostat issue - do I redo the wiring or add a transformer?

Post by Sportswhiz00 » Sat Sep 15, 2018 7:57 am

My thermostat isn’t a smart version but I can set a schedule so that the temp automatically changes at whatever times and on whatever days I program it. Might be an easy solution for you to try for 20 bucks

JoeRetire
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Re: Smart thermostat issue - do I redo the wiring or add a transformer?

Post by JoeRetire » Sat Sep 15, 2018 7:58 am

imyeti2 wrote:
Fri Sep 14, 2018 5:31 pm
We have an old honeywell round thermostat for heating only. It has the standard 2 wire thermostat wire. From all I've seen, for us to upgrade to a smart thermostat, I need the dreaded C wire.
I bought a Nest specifically because it doesn't need a C wire.

Has worked fine for years.

I got it for my weekend/vacation/retirement home in Maine so that we could monitor and adjust the temps remotely.
Last edited by JoeRetire on Sat Sep 15, 2018 8:00 am, edited 1 time in total.

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tomander
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Re: Smart thermostat issue - do I redo the wiring or add a transformer?

Post by tomander » Sat Sep 15, 2018 7:59 am

runner3081 wrote:
Fri Sep 14, 2018 7:25 pm
I would really explore the value of a "smart" thermostat. We have been using one for about a year and honestly, I could live without it.
I came to the same conclusion.

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Bammerman
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Re: Smart thermostat issue - do I redo the wiring or add a transformer?

Post by Bammerman » Sat Sep 15, 2018 9:05 am

imyeti2 wrote:
Sat Sep 15, 2018 7:49 am
My preference for a smart thermostat was to be able to check everything remotely and make changes as necessary.
If that is the main reason, perhaps you should consider a device like the Leeo (https://www.leeo.com/product). I have had one of these for a year or so and have found it useful. Using the Leeo app, I can see what the temperature and humidity is in my house (i.e., where the little device is situated in the house) and whether there are any active smoke or water/moisture alarms. Note, Leeo depends on your house having power and wifi (it will notify you if it loses power or wifi connectivity). Of course, the Leeo will not let you make any changes or interventions with your furnace or AC. What it does (in addition to measuring the temperature and humidity) s is listen for alarms and notify you if it hears any.

Oh yes, it also is a lovely multi-colored night light!

chw
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Re: Smart thermostat issue - do I redo the wiring or add a transformer?

Post by chw » Sat Sep 15, 2018 9:19 am

wilked wrote:
Sat Sep 15, 2018 6:08 am
I have two wires and a smart thermostat

Emerson Sensi Wi-Fi Thermostat for Smart Home, ST55, DIY Version, Works with Alexa https://www.amazon.com/dp/B01NB1OB0I/re ... NBbC32F4KS

Love it, works great
+1. Works great. Basic app interface, but does what you are looking for in a wifi thermostat. This is your low cost solution.

RickBoglehead
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Re: Smart thermostat issue - do I redo the wiring or add a transformer?

Post by RickBoglehead » Sun Sep 16, 2018 1:10 pm

Our electric company gives $100 rebate per WiFi thermostat. Replaced both. Can turn on/up/down temp anywhere. Today not home, checking weatherr to see if A/C needs to be kicked on.

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watchnerd
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Re: Smart thermostat issue - do I redo the wiring or add a transformer?

Post by watchnerd » Sun Sep 16, 2018 6:23 pm

Love my Nest thermostat, for the convenience, ease of use, remote connection, and ability to bring marital harmony to my life.
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