QCA-ZFA424 Application Controller

COSYS Building Controls


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

The QCA-ZFC424 is a native BACnet® controller optimized for fan coil and heat pump applications available in both configurable and fully programmable versions. It features line voltage relays for direct switching of fan motor loads, eliminating the need for external relays.
The QCA-ZFC424 communicates using BACnet MS/TP on its RS-485 main LAN port. 


  • Line voltage rated relays allow direct switching of fan motor loads
  • Local scheduling, trending and alarming support
  • Built-in configurable algorithms for quick setup and commissioning
  • Optional programmable feature allows customizations for non-standard sequences or for repurposing spare I/O
  • Service port for convenient field access
  • Firmware upgrade and database load/save over the network
  • Screw or DIN rail mountable


The QCA-ZFC424 includes built-in fan coil and heat pump algorithms that are easy to configure for typical applications.
While the QCA-ZFC424 has been optimized specifically for fan coil applications, its flexible I/O mix can easily be applied to a wide range of other terminal unit applications and configurations.
The QCA-ZFC424 is a fully programmable model that allows you to create your own completely custom zone programs, or modify the built-in algorithm’s behavior.


BACnet Device Profile
BACnet Application Specific Controller (B-ASC)

11 Universal Inputs (10-bit) supporting:
0-5 VDC
0-10 VDC
10 kΩ Thermistor
Dry Contact (using 10 kΩ Thermistor jumper setting)

3 interlocked relays for fan speed control

120 VAC: 5.8 FLA / 34.8 LRA
240 VAC: 2.9FLA / 17.4 LRA
277 VAC: 2.4 FLA / 14.4 LRA

1 SPST NO Auxiliary Relay 277 VAC, 10 A (resistive)
4 TRIAC Outputs
24 VAC, 0.5 A max each
(Switching external power)

2 Analog Outputs
0-10 VDC @ 20 mA each

35 mm DIN rail or screw mount

Device Addressing
Set via DIP switches and jumpers, or software setup

Screw-type terminal connectors on baseplate
Relay terminals 28-35 Class 1
All other terminals Class 2

Wiring Class
NEC Class 1 (Relay terminals 28-35)

NEC Class 2 (All other terminals)

24 VAC 50/60Hz @ 100 VA (15 VA excluding Power Out loading)

ARM Cortex M3 CPU

Communications Ports
RS-485 NET1
BACnet MS/TP at 38400 or 76800 bps

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

15.0 x 12.5 x 4.0 cm (5.9 x 4.9 x 1.6 in.)

335 g (0.74 lb)

Enclosure Protection Rating

CE-EMC Directive 89 / 336 / EEC
FCC Class B


Order according to the following product numbers:

QCA-ZFC424    Configurable Fan Coil Controller—24 VAC power, 4 universal inputs, 2 analog outputs, 4 TRIACs and 4 relay outputs

QCA-ZFCP424  Programmable Fan Coil Controller—24 VAC power, 4 universal inputs, 2 analog outputs, 4 TRIACs and 4 relay outputs