REASONS TO BUY
Stylish
Accurate
REASONS TO AVOID
Very expensive
Seemed a little buggy to us
Johnson Controls GLAS Review
This expensive thermostat looks great but its performance left a bit to be desired
The GLAS thermostat by Johnson Controls.
Credit: Johnson Controls
By David Wise ⋅ Senior Review Editor ⋅ October 2, 2018
Contributions From: Austin Palmer
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Our Verdict
Finishing close to the top of the group, the GLAS is a solid thermostat, but couldn't quite topple our top recommendations. It has a particularly sleek and stylish design that stands out from the rest, but we found the looks of this product to be very dependent on the type of walls you have and how clean it is — we found it to be a total magnet for dust and fingerprints. It does stand out by having a built-in set of air quality sensors and works with both Alexa and Cortana and is very accurate. Unfortunately, it is also one of the most expensive thermostats we have tested to date and its overall operation seemed a little buggy and less user-friendly than some of the top models. It might be a great bet if you absolutely love the look — and live somewhere with perfect walls, but otherwise, you are probably best served by another model.
Our Analysis and Test Results
This model finished right behind the Nest Thermostat E and the Nest Learning Thermostat. The GLAS is a bit harder to install, is slightly less accurate, and is a little bit harder to operate overall, but it is by far the most expensive.
The GLAS has quite a unique aesthetic.
Credit: Jenna Ammerman
This product is decently easy to use, but does accumulate fingerprints like crazy.
Credit: Jenna Ammerman
Ease of Use
Once the thermostat is mounted to the wall, the initial configuration is straightforward, with clear prompts guiding you through the entire process. The time and date set automatically when the device is connected to WiFi, though you do need to set which time zone you are in. There aren't many advanced settings to configure, but the single menu of additional settings is relatively easy to navigate and user-friendly.
The settings are laid out in an intuitive and user-friendly way.
Credit: Jenna Ammerman
It also is very easy to adjust the current temperature setpoint by tapping it and then using the arrow icons.
Adjusting the current temperature is done by tapping the smaller number and using the arrow keys that appear.
Credit: Jenna Ammerman
The scheduling is a little finicky, as you set the temperature for when you are home and away, then set what times you plan on being at home, rather than setting different temperatures for specific times.
The scheduling isn't the most intuitive.
Credit: Jenna Ammerman
The information displayed on the GLAS is clear and easy to read, with the option to adjust the brightness to maximize visibility for your home's lighting situation. However, the screen seems to be an absolute dust magnet and holds fingerprints very well, making relatively frequent cleaning a must.
This thermostat does have an exceptionally nice display.
Credit: Jenna Ammerman
If you are embracing the smart home side of this product, it can interface with both Microsoft's Cortana and Amazon's Alexa, though we did find Alexa to have a bit of an edge at the time of writing. This thermostat also has air quality sensors and can activate the fan according to their reading, as well as run some auxiliary appliances, such as a humidifier or dehumidifier.
The transparent nature of this product makes it a bit more work to install.
Credit: Jenna Ammerman
Install & Support
We found the customer support to be quite helpful, although it did require a few back-and-forth emails until we resolved some of our smart home issues. The standard installation process is quite pain-free, with one exception, and there are guided prompts in the app and on the thermostat to lead you through it.
The setup process, once it is mounted, is made quite easy with a series of prompts.
Credit: Jenna Ammerman
The primary challenge with installing this thermostat is the limited space available. You have a much smaller space to work with, as the wiring is all done through the non-transparent part of the thermostat. This also means that this thermostat won't do the best job of hiding imperfections or damage from your old thermostat's mounting method, so some touch-up work may be required before installing the GLAS.
The white trim plate can be used to hide imperfections on your wall.
Credit: Jenna Ammerman
Remote Access
The mobile app is very intuitive and easy to use — essentially an almost exact mirror of the interface on the thermostat itself. You can't make any equipment adjustments remotely, but you can update or reset the device. Additionally, some of the settings are even more consolidated on the mobile app, requiring you to navigate through fewer submenus to perform tasks like activating “Vacation” mode.
Testing the accuracy of this thermometer using a precision thermostat.
Credit: Jenna Ammerman
Accuracy
This thermostat typically displayed a temperature within a single degree of our control, although we did notice larger discrepancies for a short period immediately after the thermostat was installed — these usually abated within a matter of hours.
Value
This product is a budget pick, being one of the most expensive we have seen, and forces you to pay a premium price for its looks.
Conclusion
We were very excited about the prospects of this thermostat and ended up coming away disappointed. This device performed quite well overall, but its excessively premium price doesn't quite justify its second or third tier performance, precluding us from recommending it.
—David Wise and Austin Palmer
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