Training centre mechanical room

[imtiboy]

I WOULD LIKE SOME HELP REGARDING THE DESIGN OF A TRAINING FACILITY IN SAUDI ARABIA. THE FACILITY HAS A MECHANICAL A/C ROOM CONSISTING OF 5 NOS. AIR HANDLING UNITS (AHU), CHILLED WATER TYPE.<br>EACH AHU IS OPERATING CONTINUOUSLY AND INDEPENDENTLY SERVING A PARTICULAR OCCUPIED ROOMS AND IS CONTROLLED BY AN INDIVIDUAL THERMOSTAT<br>THE RETURN AIR SYSTEM OF THESE AIR HANDLING UNITS (ALL 5 OF THEM) IS COMMON USING AN IN LINE RETURN AIR FAN AS A MEANS OF RETURNING THE SUPPLIED AIR FROM THE OCCUPIED ROOM SPACES TO THE MECHANICAL ROOM.<br><br>1.HOW DO U CONTROL THE OPERATION OF THE COMMON IN-LINE RETURN AIR FAN IN RELATION TO THE OPERATION OF THE 5 NOS. AHU?<br><br>2.SUPPOSING ONE OR TWO OF THE AHUS' ARE SHUTDOWN , WOULD YOU CONSIDER A RELIEF AIR DAMPER TO BE INSTALLED AT THE MECHANICAL ROOM TO AVOID THE OVER AIR PRESSURE OF THIS ROOM.<br><br>3. THE MECHANICAL ROOM IN THIS CASE WAS BEING UTILIZED AS A COMMON MIXING BOX. HOW DO U SIZE THE FRESH AIR LOUVRE FOR MAKE-UP AIR SYSTEM? CAN IT BE AUTOMATICALLY OPERATED?<br><br>LOOKING FORWARD TO RESPONSES TO THIS QUERY. <br><br>thanx

 

[kmuhsen]

Hello <br><br>you can solve the first proplem by using a fan which driven by a variable speed frequency driver.<br>This can reduce the fan speed when the air pressure in the return duct increased.<br>i beleive both the first and the second problem could be solved by this technique.<br><br>regards,<br><br>Khaled Muhsen