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.