QCA-Z403 Thermostat

COSYS Building Controls



Our COSYS Application and System Controls work along with our enterprise software platform OspreyFMS to provide a meaningful context.

TheQCA-Z403 network thermostat combines local room sensors with a fully programmable controller with 3 universal inputs and 4 binary outputs. The Z403 also offers a choice of back-lit colors that provide additional user feedback and aesthetic appeal. The Z403 NFC technology enables installers to use NFC-enabled mobile devices to configure the thermostat on the wall or in its shipped box.
The Z403 delivers custom solutions specific to the needs of each market, and provides building occupants with an intuitive touch-interface to adjust their individual comfort levels. The Z403 customizable button overlays also allow the thermostat on the wall to match customer decor and branding.


  • Native BACnet® firmware
  • Standard RGB back light allows choice of colors to indicate conditions, alarms and night mode
  • Large easy-to-read LCD screen. Onscreen visual feedback on button selection
  • Multiple button and slider layout options. Custom button design available through Partner Applications Services (PAS)
  • Support for custom sequences through GCL+ programming
  • Support for local scheduling, trending and alarming
  • Binary outputs switch AC or DC, with internal or external power options
  • USB Service port, software enabled or disabled. Service tool not required
  • Smartphone and tablet integration and setup using NFC technology
  • Fits most electrical boxes worldwide
  • 2-piece design with tamper set screw lock


The QCA-Z403 is suitable for controlling a wide variety of basic unitary equipment. The Z403 is ideal for tri-state or time proportional valves and electric heat control, or packaged unit integration in applications like heat pumps, simple RTUs, VAV/VVT, Fan Coils, Unit Ventilators, Chilled beam and radiation. Custom sequences allow full use of all outputs for additional control of exhaust fans, lighting and blinds control or a supplementary heat stage.

The optional humidity, motion and CO2 sensors allow advanced control strategies such as demand control ventilation, energy savings based on occupancy and optimal user comfort.


External Inputs
3 Universal Inputs (12-bit), software configurable for:
0-5 VDC
0-10 VDC
10 kΩ Thermistor
Dry Contact 

External Outputs
4 SSR (FET) Outputs

24 VAC/DC @ 0.5 A max (internal or external powered)

2-line custom segmented display with icons

2 rows of 4 capacitive touch zones, allowing up to 8 individual buttons or combined to form larger buttons

RGB LED back light for multicolored LCD and button illumination

Digital Temperature Sensor
+/- 0.2° C (+/- 0.36°F)

Digital Humidity Sensor (Optional)

Accuracy +/- 3%

CO2 Sensor (Optional)
Dual Beam, Self Calibrating NDIR Detection
Range: 0-2000 ppm

Accuracy @ 25°C (77°F): ± (50ppm + 2% of value)

Temperature Dependence: 2ppm/°C
(1 ppm/ °F) typical
Pressure Dependence: 0.13% of reading per mm Hg
Stability: 20 ppm/year (typical)

Occupancy Sensor (Optional)
Passive infrared motion (PIR) sensor Range: 5m (16.4 ft.)
Coverage: 100° Horizontal

Screw-type terminal connectors

Wiring Class
Class 2 / SELV

24 V AC/DC

Typ. 4 VA / 1.2 W Max. 52 VA / 72 W

RS-485 port
BACnet MS/TP (up to 76800 bps)
USB Service Port
Near Field Communication (NFC) Passive 2-way short range

0° to 55°C (32° to 131°F)
10 - 90% RH (non-condensing)

With SM backplate:
13.3 x 9.3 x 2.3 cm (5.3 x 3.6 x 0.9 in.)
With SC (CO2) backplate:
13.3 x 9.3 x 4.3 cm (5.3 x 3.6 x 1.7 in.)
Mounted Surface Profile
Surface Mount (SM, SC backplates): 2.3 cm (0.9 in.)

175 g (0.39 lbs)
IP Rating

FCC Class B


Order the QCA-Z403with the desired options according to the following product numbers:

QCA-Z403C          CO2 Only

QCA-Z403HM     Humidity and Motion

QCA-Z403CHM   CO2 , Humidity and Motion