CIAT FLOWAY ACCESS - Page 20

Minimum ow rates according to the unit model:
P1 P126
Unit model minimum ow rate
1000 Alu 500 m
3
/h
1000 PP 500 m
3
/h
2000 Alu 1000 m
3
/h
2000 PP 1000 m
3
/h
3000 Alu 1500 m
3
/h
3000 PP 1500 m
3
/h
5000 Alu 2000 m
3
/h
7500 Alu 3000 m
3
/h
Fan delay
If the electrical heater is in operation and a unit shutdown request appears, a settable post ventilation (P164)
is used for cooling the electrical heaters
164 Fan delay time
3.8.4 - Direct expansion coil scenario
The unit is started up if the DX unit requirement is greater than 10%, and the unit is shut down when this request is at 0%.
The unit then regulates its output between its minimum and maximum levels. If two DX units are present, the two are controlled in
parallel (same 0-10 V control).
DX unit run control
DX unit
requirement
On
O󰀨
0 % 10 % 100 %
DX unit requirement
0
1V
10V
10% 100%
DX actuation voltage
Defrosting management
If the unit starts a defrosting phase, (P446 = active), the unit adapts its ow rate/pressure according to the mode selected with
P286:
- None: the unit continues to operate as per its setpoint
- Derated mode: the unit reduces its ow rate or pressure to the setpoints P287, P288 and P289
- AHU shutdown: the unit is shut down during defrosting
Minimum ow rate
A minimum air ow rate is required to use the DX coil (P126). If the ow rate is less than this parameter, the DX coil will not be able
to start up and a "control limited" message will appear.
P1 P126 P287 P288 and P289
Machine size Coil minimum ow rate
Defrosting pressure (P104 = pressure)
(P286 = Reduced mode)
Defrosting ow rate (P104 = Flow rate)
(P286 = Reduced mode)
1000 Alu 580 m
3
/h 100 Pa 450 m3/h
1000 PP 580 m
3
/h 100 Pa 450 m3/h
2000 Alu 940 m
3
/h 100 Pa 600 m3/h
2000 PP 940 m
3
/h 100 Pa 600 m3/h
3000 Alu 1500 m
3
/h 100 Pa 900 m3/h
3000 PP 1500 m
3
/h 100 Pa 900 m3/h
5000 Alu 2600 m
3
/h 100 Pa 1000 m3/h
7500 Alu 3000 m
3
/h 100 Pa 1500 m3/h
3 - FEATURES
FLOWAY ACCESS EN-20