Fresh Heaven laminar airflow units (LAF) supply clean air in a low-turbulent and vertical flow into the clean zone. Thus the contamination of sensitive areas and equipment can be held at a minimized level.

• Operating principle:

Treated fresh air (from an air handling unit) or return air from the room is driven into a pressure chamber fitted with HEPA filters, which are installed horizontally across the entire area of the pressurized field. After passing through the HEPA filters, the cleaned air is pushed through outlets along individually arranged lighting to create a protection zone around a product. Afterwards, contaminated air is extracted from the room into a central air handling unit or supplied via the power module.

Casing:

• is equipped with sensors for measuring aerosol concentration from the pressure chamber (leak test)
• is made of a welded and sealed frame made of stainless steel profiles
• top and side panels are made of: painted steel (RAL 9010) or stainless-steel (V2A ~AISI 304 stadard, V4A ~AISI 316L optional)
• height 450 / 550 / 750 mm (FHM / FHM P / FHM PB)

The unit is available as follows:

• Fresh Heaven MAXX: a unit without fans, with air supplied by AHU.
• Fresh Heaven MAXX POWER: a unit with fans (POWER module) that recirculates air from the clean room.

Fresh Heaven MAXX has two design versions:

• FHM V: air supply inlet is vertical (located on the top).
• FHM S: air supply inlet is horizontal (lateral).

Fresh Heaven Maxx dimensions:

• The height of the casing of Fresh Heaven MAXX is 450 mm.
• The maximum area of a laminar airflow field is 8.8 m², and the maximum length of the laminar area is 4.0 m.

A Fresh Heaven MAXX POWER unit is equipped with a POWER module, fans for air recirculation, and a pre-filter. Fresh Heaven MAXX POWER has 8 design versions, including various options of POWER module, pre-filters, and cooling:

• FHM PU: a horizontal suction grille mounted flush with the false ceiling.
• FHM PUC: a horizontal suction grille mounted flush with the false ceiling, equipped with a condensation-free water cooler.
• FHM PS: a vertical suction grille mounted below the false ceiling.
• FHM PSC: a vertical suction grille mounted below the false ceiling, equipped with a condensation-free water cooler.
• FHMPT: with a tower suction chamber with an air intake performed above the floor.
• FHM PTC: with a tower suction chamber with an air intake performed above the floor, equipped with a condensation-free water cooler.
• FHM PDC: with a tower suction chamber with an air intake performed above the floor, equipped with a condensation-free water cooler, and equipped with fans installed in pairs above each other to increase the length of the laminar airflow field.
• FHM PB: structural design of Fresh Breeze (fan-filter units), air suction on the upper side of lateral panels, installation over RABS (Restricted Access Barrier System) or suspended, possibility to create larger assembly groups (e.g., over production line).

Fresh Heaven MAXX POWER dimensions:

• The height of Fresh Heaven MAXX POWER is 550 mm (except for FHM PB, which is 750 mm).
• The maximum size of the unit is limited by the volumetric flow rate of 12,000 m³/h,which at the average outlet speed of 0.45 m/s corresponds to the laminar airflow field area of approximately 7.4 m².
• If a water-based coil is added to the suction chamber, the maximum volumetric flow rate is reduced to approximately 8,000 m³/h, which at the average outlet speed of 0.45 m/s corresponds to the laminar airflow field area of approximately 4.9 m².

Outlets:

• electrochemically polished and perforated stainless steel (40 % clear surface)
• perforated steel (40 % clear surface) RAL 9010 painted
• single-layer polyester fabric laminarizer (aluminum frame + stainless steel edge)

HEPA / ULPA filter in an aluminum frame, with U-shaped seal or a gel gasket and protective grid on filter’s clean air side. The filters are available in following filtration classes:

• H13
• H14
• U15

Suction grilles:

• electrochemically polished and perforated stainless steel (40 % clear surface)
• perforated steel (40 % clear surface) painted in RAL 9010

Pre-filter:

• M5 class for treatment of return air (valid only for FHM P version)

Lighting:

• powerful light-emitting diode (LED)
• compact dimensions (40 mm wide)
• smooth plastic U-shaped diffuser for optimum air flow
• economical, maintenance-free, long service life
• safe voltage 12 VDC (+ power supply 230 VAC)
• lighting intensity min. 500 lx (higher on customer’s demand)

PVC soft wall (curtain) to maximize the laminar air-flow zone:

• PVC soft wall curtain with strips in antistatic finish, thickness = 2 mm, width = 200 mm, any length
• Soft wall as one peripheral screen, 5 mm thick with varying width
• PET-G screen thickness = 4 mm, standard length 300 mm
• Safety glass curtain

Cooling coil (if applicable):

• coil is operated in condensation-free mode
• pipes and fins are made of copper, the casing is made of stainless steel
• coil is designed on the basis of parameters provided by the customer (e.g. temperature and humidity of outlet air and heat load)
• valve assembly as an option, consists of a three-way mixing valve with an actuator, a circulation pump and a balancing valve
• Several FHM P units (installed next to each other) can be supplied from a single valve assembly (each coil must have its own balancing valve)

Various options for unit controls:

• local control via display
• remote control using a Building Management System (BMS) and potential-free digital inputs and outputs
• combined options with local display and BMS
• monitoring option for Fresh Heaven MAXX unit series

Controls:

• switch box is mounted on the side of the Power module and has following dimensions: 600 (length) x 300 (height) x 150 (depth) mm
• control module (“Siemens Logo!”) performs following functions: filters replacement indication, lighting switch, air speed alarm, switchover between the nominal and reduced air flow mode
• pressure switch for HEPA filters
• pressure switches for pre-filters (valid for FHMP version)
• power supply for LED lights
• potential-free outputs to the central Building Management System (BMS) as an option