Call +91 90565 90909
Call +91 90565 90909
FLEXE
Bespoke, centralized air handling units
Airef manufactures world-class, bespoke (customized) AHUs in highly flexible configurations, tailored to meet the varying HVAC requirements of modern buildings. A variety of functional modules can be logically clubbed to form an AHU, optimized to achieve the required indoor parameters. 'Flexe' can be manufactured in numerous configurations, with or without the use of energy recovery devices.
Range: 1000 CFM to 46000 CFM
Applications: Pharmaceutical clean rooms, Operation theaters, Hospitals, Hotels, Food growing and processing areas, Shopping complexes, Production areas, Office spaces, Apartments and other commercial or industrial facilities.
Features:
a. Customized models for varying indoor needs
b. Large choice of functioning modules
c. Large choice of component types like casing, fans, filters, coils etc.
Options:
a. Space-saving, 2 tier units
b. Cold-bridge free, frameless design
AIRFLOW DIAGRAM - FLEXE
Range: 1000 CFM to 46000 CFM (27 Sizes)
INSULATED CASING
Standard casing panels are sandwich type with Polyurethane foam (density not less than 40 kg/m3) pressure-injected between two metallic skins. These panels are fitted onto extruded Aluminum frame using EPDM gaskets. High quality nylon fittings, plastic handles, Aluminum hinges and viewports are used in making the casing.
Standard casings available are:
TB50: Thermal break type extruded Aluminum mainframe with 50 mm thick double skinned panels
TB25: Thermal break type extruded Aluminum mainframe with 25 mm thick double skinned panels
NTB25: Standard extruded Aluminum mainframe with 25 mm thick double skinned panels
Specially designed frameless thermal break casing is also available.
Standard grid type base frame is made of 1.5 mm thick galvanized steel (powder coating optional) with powder coated lifting corners. High quality and easy to use handles are provided as standard. Safety kit consisting of LED light, limit switch and view port is provided in the fan section as a standard.
FANS & MOTORS
A variety of fan-motor combinations are available as per the requirement in terms of airflow, static pressure, drive mechanism and functionality:
DIRECT DRIVEN PLUG FANS
Directly coupled to TEFC induction motors (Efficiency class IE02 / IE03 / IE04).
DIRECT DRIVEN EC PLUG FANS
Having integrated VFD and electronically commutated (EC) motors (Efficiency class IE04 / IE05).
BELT DRIVEN SCROLL FANS
Run using TEFC induction motors and pulley arrangement (Efficiency class IE02 / IE03 / IE04).
DIRECT DRIVEN SCROLL FANS
Run using directly coupled split-capacitor type multi-speed motors (Efficiency class IE02).
FAN WALL
Multiple fans are arranged in parallel to form an array and are controlled with one signal.
For special applications, Atex certified / flameproof motors are also available. In such units, the limit switch and LED light are also supplied in flameproof construction.
HEAT EXCHANGERS (COILS)
Various types of heat exchangers (cooling / heating) are available depending upon the requirement:
WATER TYPE
Hydronic coils use hot or chilled water, running in Copper tubes, mechanically bonded to Aluminum fins.
DIRECT EXPANSION (DX) TYPE
Suitable for high pressure refrigerants (like R410), these coils have internally grooved Copper tubes, mechanically bonded to Aluminum fins.
STEAM TYPE
High pressure steam is used in these coils, having welded stainless steel tubes, mechanically bonded to Aluminum fins.
ELECTRIC HEATER BANK
Finned type electric strip heaters are provided in staged structure via electrical isolators.
Standard coil casing is galvanized sheet. Special coils with SS304 casing, Hydrophobic/Hydrophilic fins and corrosion resistant coatings are also available.
Standard condensate-drain tray is sandwich type with SS304 sloped inner pan, 13 mm closed-cell Nitrile rubber thermal insulation and pre-painted galvanized steel secure-skin.
HUMIDIFIERS
Different types of humidifiers are available to add moisture to the supply air stream:
CELLULOSE PAD TYPE
Water is sprayed over rigid cellulose pads, which is then collected in SS304 sump, to be recirculated using suitable pump and piping arrangement.
SPRAY TYPE
Multiple banks of high-pressure nozzles add mist to the supply air stream. PVC drop eliminators are used to prevent the excess water carry-over.
STEAM PIPE TYPE
Stainless steel pipe with orifices is introduced in the air handling unit, through which steam coming from the steam generator is added to the supply air stream.
PAN TYPE
Steam is generated in a stainless-steel pan with integrated heaters inside the air handling unit, added directly to the supply air stream.
FILTERS
Single or multiple stage filter walls are used to remove unwanted particles from the air stream. The filters are easily removable and replaceable without the use of any special tools. All our air handling units use 'AAF' brand filters by default.
PANEL FILTERS
Metal mesh Aluminum course filters - Grade G2
Pleated non-woven media filters - Grade G4
EXTENDED SURFACE BAG FILTERS
Secondary filters with non-woven media - Grade M5 / F7
EXTENDED SURFACE CASSETTE FILTERS
Pleated non-woven media filters - Grade M5 / F7 / F9
Pleated hybrid non-woven media 'V-Bank' filters - Grade F7 / F9
Pleated fiber glass media filters (HEPA) - Grade H13 / H14
All filters (except V-Bank filters) have Aluminum casings and frames by default. Application-specific filters with SS304 casing, Gaseous-phase media filters, Chemical filters, Carbon filters and Electrostatic filters are also available.
AIR MIXING MODULES
Following types of modules are provided to mix air before it enters the treatment section:
SINGLE MIXING BOX
Most commonly used mixing box, to mix return air and outside air (fresh air) in order to achieve desired balance of cooling / heating, room pressure and CO2 level. This mixing box uses a two-damper arrangement.
DOUBLE MIXING BOX
This type of mixing box is generally used in two-fan systems, to mix partial amount of return air with the outside air, before exhausting the rest to the atmosphere. This mixing box uses a three-damper arrangement to accurately balance the room pressure.
All volume control dampers are made of gasket sealed, gear operated, extruded Aluminum blades. The dampers can be operated manually as well as using an actuator.
SOUND ATTENUATION
Silencers mechanisms can be integrated into the units for low overall sound level in the treated room. Following are the options available:
THERMO-ACOUSTIC CASING
The casing panels are made with a combination of thermal insulation and an acoustic lining, especially in the fan section. The acoustic lining is covered with perforated metallic sheets. The commonly used acoustic material is 10-20 mm thick open-cell Nitrile rubber.
SILENCERS
Generally fixed at the supply end of the air handling unit, the silencers are made of open cell rockwool filled in a galvanized steel frames and covered with perforated metallic sheets. The frames are shaped to have low pressure drop.
HEAT RECOVERY DEVICES
Following devices are available to recover the energy from exhaust air stream and transfer it to the outside air (fresh air) stream for pre-cooling:
ROTARY HEAT EXCHANGERS (HEAT RECOVERY WHEELS)
Used for total recovery (latent + sensible), the heat recovery wheels are made of Aluminum core, coated with desiccant material such as silica gel. The general efficiency of these devices goes up to 80%. The wheel is run using an electric motor.
RECUPERATORS (PLATE HEAT EXCHANGERS)
These are static type of recovery devices wherein exhaust air and supply air streams are passed through alternates channels of Aluminum or polymer-based core, thus exchanging the energy without mixing. The general efficiency goes up to 70%.
INTEGRATED CONTROLS
The 'Flexe' series is available with integrated control panels, with or without micro-processor (PLC) based controllers, with the following options:
FAN STARTUP - DOL & Star-Delta
TEMPERATURE CONTROL - DX & Chilled water systems
RELATIVE HUMIDITY (RH) CONTROL - Electrical heaters & Hot water systems
AQI CONTROL - Controlling CO2 and VOC value of the room
FAN SPEED - Constant flow, constant pressure or manual VFD control
DATA LOGGING - Operation data and error log
MAINTENANCE- Setting up maintenance schedule and alerts
BMS - Seamless integration with building management systems via Modbus TCP or BACnet/IP
ULTRA-VIOLET GERMICIDAL IRRADIATION
In order to maintain the sterility of the supply air stream and to prevent the growth of micro-organisms like mold, on and around the face of cooling coils, UV-GI lamps are provided downstream of coils. Mounted on Aluminum channels or galvanized steel channels, the use of UV-C light at 254 Nm ensures a clean surface of coil and condensate tray.
FLEXE-H (HYGIENIC OPTION)
"H for Hygienic construction"
As an extension to the 'Flexe' series, specially designed 'Flexe-H' units are constructed in accordance with VDI 6022-1 and DIN 1946-4 guidelines for hygienic construction. Loaded with easy cleanability capabilities, these units are designed and manufactured specifically for pharmaceutical manufacturing areas and medical clean rooms. The use of hygienic materials resistant to disinfectants, and rounded inner edges ensure hygienic conditions for a longer time.
Special features of hygienic construction:
a. Smooth inner surfaces and rounded edges. (Corrosion class 4 - ISO 12944)
b. Sloped stainless steel drain pans
c. Use of multi-stage air filtration for clean room supply
d. Inspection window and light kit in all sections
e. Withdrawable type main components for easy cleaning
Options:
a. 70 mm casing thickness
b. Cold-bridge free, frameless design
c. Mineral wool insulation
d. Special gaseous phase filters
e. Hydrophobic coil fins with corrosion resistant coatings
f. Use of Flameproof/Atex certified motors
g. Use of UV-C lights & ISO 846 plastic parts to prevent microbial growth
