Thermostat Recommendations? Need 4x!

Hello - I just purchase ST. I have set-up a few multi-sensors, two power outlets and two Presence sensors. So far I am very impressed with UI & ease of set-up/connecting ‘things’ (acknowledging there is still work to do).

I just moved into a new high-rise condo near NYC (2bed/2bath)… so the projects begin! I will be undertaking two large ST projects over the next few weeks Thermostats & Light Switches/Outlets.

Thermostats will be my biggest investment (I will need 4x) so I was hoping you (the ST community) might be able to offer some advise. I have 4 In-Wall AC/Heat units, each has its own ‘dumb thermostat’ (6100 series on this page – very frustrating with simply on/off + temp setting thermostats as I have left 1 or 2 on by accident many times over past few weeks and it shows in my 2nd electric bill.

I am primarily looking to add remote connection to ensure I turn off thermostats when I leave and to be able to turn them on when I am heading home (my schedule varies significantly). Any input on which of the ST compatible thermostats are best to go with? I have looked at list of compatible and fairly short list and unimpressed with some of options

  • RCS TZ35: ~$132 (x4= $528)
  • Honeywell zw1007: ~$132 (x4= $528)
  • Ecobee Smart Si $169 (x4 = $676)

To me is seems the Ecobee is a no brainier for little bit extra cost. Any suggestions here or other options ST is working on? (wish there was a <$100 out with ability to have 7 days program – don’t want to just rely of z-wave schedule and 1 set-temp hence why I didn’t include the Radio Thermostats)

I love my two Ecobee Smart thermostats :slight_smile:

Thanks darrylb! I checked last night and have 24v at the panel, so I should be okay with any of these set-ups. With that said how was ease of install? Any way for me to tell if my set-up is compatible? (Tried to attached a pic of what my current tstat has linked but said ‘new users cannot past images’ so I can say I have the following wires R, C, W, Y, G, B)

Also do you have Ecobee Si? Do you find the smaller screens large enough to view current temp/weather info?
I just see the Ecobee Stat-02 @$254 toooo costly when I have to buy 4… Again ideally I would love if there was a <$100 z-wave tstat that was compatible

I use the Smart Thermostats, not the Si. So I have the large screens.

As for compatibility, I would reach out to ecobee support, they are very easy to reach and quick to respond. I suspect you have the adequate wiring, but I have only limited experience.

Good morning, my name is Mu and I work at ecobee. Please send me an email at and I would love to answer all your questions and help you out. We’ll make sure we can find the best price for you for 4 Smart Si thermostats.

Looking forward to hearing from you.


Thank you for your comment. I’m really glad you like your ecobee smart thermostats. I would love to chat further with you too. If you don’t mind, please get in touch via email:


Thank you darrylb and ecobee for the quick replies! I have reached out to the ecobee team to see if they can advise on compatibility.

Will keep the community updated with my decision & final pics of my set-up!

I’m glad to see I’m not the only one with this challenge. We have 6 thermostats.

We have radiant floor heating and no AC. We live in Summit County, Colorado, so the lack of AC is never a problem (at 9100 Feet). But it take a while for the heating to come up, and cool off, and I would really like to automate it, with out giving up the ability to have different zones.

A cheap(er) and efficient solution would be great!

Does anyone have experience with the 2gig CT100 Z-Wave Programmable Thermostat?

They are a sub $100 thermostat, and might be a lower cost solution for those of us with weird thermostat setups.

I ended up purchasing 4x ECOBEE Smart Si Thermostats at $160 each. Large upfront investment but loving the SmartThings integration; although there is a significant lag with tiles displaying thermostat data on SmartThings ‘refreshing’ (Can Anyone help with this?)

I love that I was able to create the rule when my phone left my home I could automatically turn the AC off! Also I have it set-up to only trigger the tstats to turn on when I get back home. July was hotter than June yet my electric bill I just got was 37% less month/month; and I would say I was more comfortable in my home.

The Ecobee tstat is more expensive but might be a good solution for you with your Radiant heat set-up (as it supports it and will probably give you greater control… does the other thermostat support your set-up?). Ecobee platform allows you to download all of your data (it logs ~5min, Temp, set point, outdoor temp, humidity, etc) this may be very helpful for you.

+1 for Jotto’s “lag” reference. My two ecobee Smart Thermostats also show a lag with the integration on SmartThings.

It seems polling has been broken for some time, and while there is a workaround for it, you should open a ticket with SmartThings support so this gets fixed.

I ended going up with CT100’s for 2 reasons:

  1. Cheaper! I got all 6 for less than $500. I reached out to the above contact to see if there was a group discount, and they only referred me to Amazon. Not all that helpful.

  2. No “C” wire. Meaning I don’t have power routed to my thermostats, so they operate on AA.

It took me a total of 5 minutes to setup, connect and sync my thermostat. It sync’d in another 5 minutes.

I’m not experiencing any lag when it comes to making changes. I raise the temp, and the heat goes on almost instantly. I should say, I have radiant heat, so it take hours to create a noticeable change, so i might not notice lag in reporting if it existed.

Now I’m working on a program to network my thermostats together.

@Mr_Matt sorry to revive this old thread but I wondered what your experience has been with the CT100 thermostat? I too am in the Colorado mountains and have a radiant floor system. Do you have any issue with overshoot or other problems with this unit?