Johnson Controls GLAS User manual

Support
If at any point you need assistance, we’re here to help.
Visit glas.johnsoncontrol.com/support for how-to videos and frequently asked ques-
tions.
Can’t nd what you’re looking for? Give us a call at 1-833-297-4527(GLAS) and our
technical team can walk you through it.
Before you start, download the GLAS app for easy installation.

Included in box
GLAS Thermostat 4 Screws
Wall Plate 4 Drywall Anchors
4 to 5 Wire Adapter Quick Start Guide
Tools required
Screwdriver
Drill
Level

Compatibility
GLAS is compatible with most 24 VAC heating and cooling systems.
Use the compatibility checker to ensure your system will work with GLAS by going to
glas.johnsoncontrols.com/compatibilitychecker.
Heating One or two stages
Cooling One or two stages
Heat Pump One or two stages with one-or-two stage auxiliary heat
Fan Single-speed fan
Auxiliary Humidier, dehumidier, or ventilator (including HRV or ERV)

Terminal descriptions
Note: If you have only one R wire, connect to RC.
Note: If you are replacing an existing thermostat, remove any jumper wires between
R and RH or RC and RH.
YFirst stage of cooling or rst stage heat pump
Y2 Second stage of cooling command or second stage heat pump
WFirst stage of conventional heating or rst stage auxiliary heat for heat pump
systems
W2 Second stage of conventional heating or second stage of auxiliary heat for
heat pump system

Terminal descriptions
GFan
O/B Heat pump reversing valve (supports both O type and B type)
AUX Auxiliary - humidier, dehumidier, or ventilator
R 24 VAC Cool
RH 24 VAC Hot
C24 VAC Common

IMPORTANT: If your thermostat is built into the wall and connected
to thick wires with wire nuts, or if it is labeled 110, 120, or 240 volts,
you have a high voltage system that is not compatible with the GLAS
Thermostat. Do not connect your thermostat to these high voltage
wires. GLAS is only compatible with 24VAC systems.

WARNING: Risk of Electric Shock.
Disconnect the power supply before making electrical connections.
Contact with components carrying hazardous voltage can cause
electric shock and may result in severe personal injury or death. If you
have any doubts about properly installing the device, please contact
a professional installer.
ADVERTISSEMENT: Risque de décharge électrique.
Débrancher l’alimentation avant de réaliser tout branchement élec-
trique. Tout contact avec des composants conducteurs de tensions
dangereuses risque d’entraîner une décharge électrique et de provo-
quer des blessures graves, voire mortelles. (need translation)

Turn o system power
2. Turn o the power to your heating or
cooling system at your breaker box to
avoid electrocution or shock.
3. If you want to check your system’s pow-
er, adjust the temperature on your current
thermostat enough that the system
switches into heating or cooling mode. If
the system does not power on in a few
minutes, it is o.
IMPORTANT: Never work with
live voltage

Check old wiring
4. Remove the front plate of your old ther-
mostat and take a picture of the current
wiring that shows the wire colors and con-
nections. This picture will come in handy
when connecting your new thermostat.

Connect optional 4 to 5 wire adapter
Note: If you have a C-wire, skip to Step 8.
If you do not have a C-wire to power your
thermostat, use the included adapter to
provide power.
5. Remove the cover of your furnace or air
handling unit to access the control board.

Connect the adapter
6. In your HVAC equipment, disconnect
wires from the control board and con-
nect them to the open terminals on the
adapter.
7. Connect the wired terminals on the oth-
er side of the adapter back to the control
board. (Mount with a included magnet)

Disconnect your old thermostat
8. Disconnect your old thermostat and
remove the backplate
Note: While disconnecting your old ther-
mostat, use drywall-safe tape to secure the
wires and keep them from falling back into
the wall.

Installing your GLAS
9. Remove the frontplate by pulling the
top of the silver cover towards you.
10. Use a level to dry t your GLAS and
mark the wall where you plan to hang
the thermostat. Then drill in the drywall
anchors.
11. Pull all of the wires through the back of
the GLAS thermostat.

Attaching your GLAS
12. Loosely attach your GLAS to the wall
using the included screws.
13. Use your level or the level displayed
on the device to straighten the thermostat
and tighten the screws. Do not overtight-
en.

Wiring your GLAS
14. Use the picture you took of your old wiring as a reference and connect the wires
to the corresponding terminals on your new GLAS. See pages 25-26 for wiring exam-
ples.
Note: If you have auxiliary devices, such as a humidier, dehumidier, or ventilator,
see pages 27-34 for wiring examples.
Note: You do not need to have a wire for every terminal.

Attach the front plate
15. Make sure any access wire is ush
against the wall and press the front plate
until you hear a click.