Thermostat Requirements

I would like to upgrade my current programmable thermostat to a network connected device. I do not want to rely on WAN servers, so that eliminates quite a few wifi t-stats such as the Honeywell models. Some requirements for my next t-stat include:

  1. direct control from a LAN device (no middleman)

It would be preferable for the t-stat to be secure in the sense that it would only accept commands from pre-authorized devices (like SSH memorizes connected devices). That being said, the HestiaPi fits these requirements.

The home can go for long stretches unoccupied: I would like to maintain humidity limits. The Radio Thermostat CT-80 has a humidity sensor and is controllable from a LAN device (maybe even OH?), however, it probably does not have the SSH server and the good security that comes along with SSH.

  1. Humidity sensor and ability to enforce humidity limits

I did not see anything that indicated that the Hestia solution has humidity control, however, I think that it would be will within its capability of to perform this task by adding the sensor and humidity logic.

I am wondering what others are doing to secure their T-stats and what are the most popular T-stat models used with OH. Any guidance or advice is appreciate with regard to selecting networked T-stats.

I see you ruled out thermostats that are monitored/controlled from a cloud service, but aside from the vendor potentially having access, the security is actually very good for thermostats like Nest and Ecobee. All comms are encrypted and authorization uses OAuth2, so no user credentials are involved in any integration. This could end up better than a less secure local LAN system that is then opened up for remote access in some other way.

But if you can’t trust Internet connectivity, cloud infrastructure or site security at the vendor’s operations, then of course you would have to look elsewhere.

Cheers, John

Plus when Nest launches Weave next year, in theory you should be able to cut it off from the cloud and access it directly over the LAN.

I’ve got a Nest and really like it. I have no immediate worries about using their cloud.

@Tinkerfailure: the $200 Radiothermostat CT-80 can be controlled directly controlled from the LAN and features humidity. Have you used the $250 Nest’s ‘cool to dry’ feature and can you comment if it is effective? I wonder if the Nest has a webserver that enables direct access / control of the Nest thermostat?

Update: Enable Nest SSH server:

No, what’s that?! Is that an air con related mode? I’ve never even heard of it, maybe it’s not available in my region (UK)?

Unclear to me what ‘cool to dry’ feature is, but as one cools a room it reduces the humidity, so I would speculate that it drops the temperature and using a humidity measurement and humidity target (goal) to continue cool until the target is reached.

I ordered the wifi-enabled RadioThermostat CT-80 because:

  1. capable of receiving LAN only commands (thermostat has a web server running on it)
  2. capable of WAN (cloud) commands
  3. humidity measurement capability

I like to have as many (good choices) as possible: capability 1) allows me to secure my device and I can remotely VPN into my network and issue commands / check status. Capability 2) enables mobile app connectivity. If I can shut capability 2) on / off then it is the best of both worlds. For more check out this good blog:

I hope to be able to use OH (OpenHAB) to use the thermostat sensors and provide alerts when conditions are adverse. BTW, I purchased it on the Radio Thermostat website for less than what it would cost on Amazon. From time to time they put them on sale, so if you can wait and bide your time that would be ideal. Unfortunately, I have a narrow window of time to buy, install and test,

@gatorback how is the ct-80 working out?