Tender Specification for Supply, Erection, Testing and ... - IDCO

F) FRESH AIR INTAKE LOUVERS WITH BIRD SCREEN:
The fresh air intake louvers at least 50mm deep will be made of powder coated extruded aluminum
construction. Bird / insect screen will be provided with the intake louvers.
The blades shall be inclined at 45 degree on a 40mm blade pitch to minimize water ingress. The
lowest blade of the assembly shall be extended out slightly to facilitate disposal of rain water without
falling on door / wall on which it is mounted.
The intake louvers shall be provided with factory fitted aluminum construction volume control dampers
in black anodised finish.
PAINTING:
All ducts collar / shoot behind the grills / diffuser shall be given at least two coats oil black enamel
paints.
TESTING:
The complete duct system shall be tested for air leakage & complete air distribution system shall be
balanced in accordance with air quantities indicated on the approved drawing.
CONTROL SYSTEM:
This section deals with supply, installation and testing, commissioning of necessary controls
(automatic) and instruments conforming to these specifications and shall be in accordance with
schedule of quantities.
The various controls listed below shall be electrically operated and in case of low voltage controls the
necessary step down transformer shall be provided with each control.
All automatic controls shall be as detailed in specifications.
CONTROLS FOR AIRHANDLER:
Three way modulating valves:
The three way modulating valves shall be provided in chilled water line to the cooling coil of Airhandlers
which is actuated by a proportionating thermostat. The three-way valve shall be selected for
valve authority value in the range of 40 % to 60 %.
These valves shall consist of bronze metal valve body with stainless steel trim with linear flow
characteristics. Modulating motor suitable for 24 volts AC supply shall be complete with 220/24 volts
transformer and shall be suitable for operation with a signal of 0-10 volt DC from the proportionating
thermostat.
The pressure drop across valve for air-handler unit shall not exceed 5.0 PSI.
The valve linkages shall be of the same make as of valves and modulating motor.
THERMOSTATS:
a) Snap Acting Thermostat for FCU:
These shall be electrically operated fixed differential type with the sensing elements located in the
return air passage. The exact mounting arrangement, profile etc. shall be derived as per location
requirements.
No of Corrections
-48-
Signature of Tenderer