Operating the fresh air supply fan
The full fresh air supply method is applied for places that do not need air conditioning but constantly need fresh air. If fresh air is required to enter the place, it may be operated together with exhaust fan. Since there will be some pressure increase in places where full fresh air operation is performed with forced air supply, the entering of polluted air from outside is obstructed. Individual control panels (Figure.9) are provided for each fresh air fan (Figure.10).
When the fresh air supply fan start button is pressed, first all air dampers open 100%. They turn off automatically at the end of the programmed time or when the smoke detector in the air-pressed room is activated due to a possible fire.
The amount of fresh air supply is provided by a frequency-controlled electric motor. Any malfunction in the main components will appear in the alarm section while the fresh air fan is running. In such cases, the fresh air fan automatically stops and all dampers close 100%.
The running values of the fresh air supply fan, started after all the command elements on the panel are adjusted by Marine Engineer, must be monitored by means of control elements.
Figure.9 Fresh air fan control panel layout
Figure.10 Fresh air supply fan operation layout
Table.2 Setting and monitoring of fresh air supply fan command-and-control elements
Sq. Element Setting/Monitoring Condition
1. Control Monitor alarm bulbs lit WHITE
2. Control Monitor RST bulbs lit RED, GREEN, YELLOW
3. Command Shift power switch ON
4. Control Monitor power bulb lits WHITE
5. Control Monitor outdoor air quality 85 %
6. Control Monitor indoor air quality 45 %
7. Command Set required air quality 85 %
8. Command Set fan start time 10:30
9. Command Set fan stop time 12:00
10. Command Shift control switch AUT
11. Control Monitor RAD position and lits …
12. Control Monitor EAD position and lits …
13. Control Monitor FAD position and lits OPEN, GREEN
14. Control Monitor MXD position and lits …
15. Control Monitor CAD position and lits OPEN, GREEN …
16. Command Push Start button, lits GREEN
17. Control Monitor fan motor bulb lits GREEN
18. Control Monitor fan motor voltage 380 Volt
19. Control Monitor fan motor current 25 Amper
20. Control Monitor fan speed 200 RPM