Co Air Quality; Fire Protection - Carrier 39HXC Manual

3 - FEATURES
3.12 - CO air quality
2
Before activating the air quality function (P152), you need to install a CO
strip situated in the electrics box. Refer to the unit's manual for the installation and electrical connection.
This function calculates an IAQ (Indoor Air Quality) requirement thanks to a proportional controller (P217) so that the CO
setpoint (P216) can be monitored.
If the fans are under flow rate control:
Air quality control acts primarily on the fresh air rate via the mixing damper (if present), if the fresh air rate reaches 100%,
the control system then acts on the ventilation flow rate, increasing the flow rate to a maximum value controlled by parameters P218
and P219.
Maximum flow rate
If the air intake fan is under duct pressure control (P104):
Warning: this function cannot be used if the heat recovery unit's frost level is monitored by a pressure sensor or if the extraction fan
is under duct pressure control.
In this scenario where the air intake fan is under duct pressure control, the air quality sensor must be connected to terminal strip
J26-U12.
The control function only acts on the opening value of the mixing damper to allow a greater influx of fresh air.
opening percentage
152
216
217
218
219

3.13 - Fire protection

When a DAD (standalone trigger sensor) is connected to the unit, the fire detection function of the control must be activated (P24).
There are several operating modes in case of fire detection:
- Unit shut down
- Intake fan forced to P282 flow rate and exhaust fan shut down
- Exhaust fan forced to P283 flow rate and intake fan shut down
- Intake fan forced to P282 flow rate and exhaust fan to P283 flow rate
24
280
282
283
ATTENTION : The fire fault management strategy must be chosen according to the regulations in force in the AHU's country
of installation. The AHU is not a smoke extraction device.
24
100%
0%
Air quality
setpoint P216
P218
Regulated flow
rate setpoint
(1 or 2)
% fresh air
100%
Mixing minimum
1/2
Air quality control
Air quality setpoint
Air quality proportional band
Air flow max setpoint on intake for air quality
Air flow max setpoint on exhaust for air quality
Fire detection
Fire safety operating mode
Intake flow rate in case of fire
Exhaust flow rate in case of fire
sensor in the exhaust air flow, and connect it to the terminal
2
IAQ requirement
Air quality proportional band
P217
0% 100%
0% 100%
Air quality
P331
IAQ requirement
IAQ requirement
concentration
2