Trane ComfortLink II XL950 Control TZONE950AC52ZAA by Trane

UPDATED - 2018 AugustThe non-technical summary:This thermostat had/has some huge security holes and Trane isn't patching them automatically.To check the firmware version: From the home screen, push "? Help" in lower left corner, then "About"Anything lower than 4.0.3 has a significant security flaw4.0.3 was released January 27, 2016 (so be sure to thank your service tech for keeping your system up to date)As others have replied (and I fully agree) these types of devices (internet connected things) are best kept on a separate wifi or vlan with restricted communications if you have the ability to do so. If not, consider if you really need your thermostat connected to the internet (probably not). Understand there is a real risk that your home network can be hacked and anything connect is at risk (phones, tablets, computers, etc.).Suggested googling:1) trane thermostat security2) Talos Blog - Trane IoT VulnerabilitiesThere were 3 significant flaws in 2014.Trane finally created a fix in 2016, BUT CHOSE NOT TO NOTIFY CUSTOMERS OR AUTOMATICALLY UPDATE SYSTEMSOriginally these thermostats could automatically update their firmware over wifi but Trane has stopped that.Customers could also download updates and install it themselves. Trane has stopped that.Currently updating requires a Trane Tech to manually update the system (and many don't know how)Timeline per Talos article:2014-04-09 - Initial contact with Trane is established. Advisories delivered.2014-06-03 - Second attempt to contact Trane for follow up. No response received.2014-08-15 - Third attempt to made to contact Trane for follow up. No response received.2014-09-30 - Fourth attempt to contact Trane is made. Advisories re-sent. No further correspondence.2015-04-?? - Vendor patches CVE-2015-2868 in firmware version 4.0 without issuing a security advisory.2015-05-26 - CERT/CC notified. CERT attempts to establish contact with Trane, but receives no response.2015-07-13 - Fifth and final attempt to contact Trane is made. Communication is reestablished. Advisories re-sent.2015-08-19 - Talos follows up with Trane. No patch available.2015-09-30 - Talos follows up with Trane again. No patch available.2015-10-19 - Talos follows up with Trane again. No patch available.2016-01-26 - Talos follows up with Trane again. Trane informs Talos that firmware version 4.0.3 is being released that week which addresses CVE-2015-2867.2016-01-27 - Trane makes firmware version 4.0.3 available to the public.2016-02-08 - Talos and CERT/CC disclose these vulnerabilities.ORIGINAL - December 2014I received this as part of a new Trane HVAC system. To be brief it is pretty (love the big color screen) and has techie 'wow' factor, it is also very easy to use AFTER it is setup and has more features than most need. Setup is neither intuitive nor difficult. There are many advanced features to play with or mess up.Two Problems:1) This "future proof" device does not support 10 year old networking standards (doesn't allow WiFi passwords > 31 characters). I am disappointed and amazed that a premium product requires owners to degrade their Wi-Fi security.2) Display size not documented, probably because this "high-definition" screen is 640x480. 640x480 = VGA and on a 7 inch screen that's about 82DPI (far worse than original iphone or any modern tablet).It may be one of the best currently available but it is grossly overpriced (iPad mini 3 = $399).4-star would require modern screen and Wi-Fi security standards5-star would require intuitive menu (no instructions/manual needed)

First, I got this as part of a new furnace and a/c system from my contractor, who recommended it highly. So, I didn't get it through Amazon.However, I would urge extreme caution before selecting this thermostat.It replaced a Nest thermostat, which I liked a lot.But this thing is bat{blank) crazy.I've been playing whack-a-mole with it continuously, trying to keep my house warm. What setting to use? Well, anything below 77 is generally too cold. 77, seriously? I was comfortable with my Nest set at 74. Eventually found that 80 was okay. For a while. Then that was too cold, so I had to take it up to 81. Hours later, it's far too hot in the house. Took it down to 78. OK for a while, then it got too cold. Tried 79. Nope. 80? Good. For a while. Left the house for several hours, so I dropped it down to 76 while I was gone. Surprisingly, it was nice when I returned. A while later, the house got too cold again. It's connected to Trane's top of the line fully variable furnace and air handler. I certainly wouldn't use it with anything else, and am having doubts about using it with Trane gear. On the plus side, the display is nice.

I echo the post of the writer STONE.Very pretty to look at. Not a NEST or Lyric but in a cheap Android tablet way.Is proprietary for operating Trane variable speed & communicating HVAC components ($$$$).Has lots of HVAC options that can be adjusted esp. if you have a reciprocating communicating Trane AC, Heatpump or Air handler.I have the Trane air handler only...but If I also had one of the other 2 Trane components, then I could really change things up.Alas, I can only affect airflow with my setup....And unless one is a certified HVAC professional, one can mess up their comfort & energy efficiency by changing too many things under the installer's menu...but I digress.Having said that, this was part of my Trane HVAC package from my builder & in my North East located house it has really optimized our comfort & heating/cooling to where we don't sweat or freeze & our bills are greater than 50% less than what they were prior (other factors are involved not just the XL950).While the 950 can schedule by hours/days/weeks like other t-stats out there, I like that I can:1) control my home's 3 individual zones with their remote dampers on just one controller.2) increase/decrease number of cycles that is run each hour (this is good for comfort & equipment longevity)3) control the t-stat temp settings & override my schedules via a web page or a mobile app offered for free by Nexia (Nexia charges a monthly fee if you add other things like lights/cameras/security to the t-stat -which I don't need).4) see 5 day weather forecast, current conditions & weather alerts5) connects via WiFiCons:1) Not as many software updates as I would like but then I figure the HVAC equipment plays a LARGE part of determine this vs. end user experience.2) Interface is really slow to process esp. when you type in the settings3) Moving from one screen to another is also slow page to page process4) Wish it had a geofencing proximity sensor that would start the HVAC as I am getting close to home vs. just going by the schedule (ala the Lyric) since schedules change all the time.Overall - Trane could have made this easier to use & faster to operate for the average Trane home owner but I guess they have to keep a source of revenue for their HVAC pro business partners.