Pure Air Circulator Unit

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 Easily check or replace filters by opening the drawer on the PACU2 unit.

• Three-Stage Filtration System Includes Desiccant Filter, 15 µm Particulate Filter, and 13X Molecular Sieve
• Ideal for Applications that Benefit from a Pure and Clean Atmosphere
• Optional 19" Rack Mountable Version Available by Contacting Tech Sales
• 4 m of Low-Outgassing Tubing is Included with the Device (Additional Tubing is Available Below)

The PACU2 Pure Air Circulator Unit is a closed-loop filtration unit that consists of several filters designed to remove moisture and particulates from the air. It is ideal for the continuous filtering and circulation of extremely clean, dry air in an optical cavity. The three filters included with the system are the desiccant and 4 Å molecular sieve filter, 15 µm in-line particulate filter, and a 13X molecular sieve with desiccant filter. 

Pull up on the handle lock on the front of the unit and pull open the drawer to access the filters and internal components. The desiccant of the PACU2F1 and PACU2F3 filters can be assessed for saturation once the drawer is open by checking the viewing window on the filter housing. Pink desiccant indicates that it is saturated and the filter should be replaced. If the filters are saturated, the airflow will be reduced as indicated by the flow meter. Filter replacements for this unit can be purchased separately below. Alternatively, the desiccant can be regenerated by following the regeneration instructions in the manual.

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Pink, Water-Saturated Desiccant as Viewed through the PACU2F1 Filter Window

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Blue, Unused Desiccant as Viewed through the PACU2F1 Filter Window

• Direct Replacement Filters for the PACU2 System:
  • PACU2F1 Desiccant and 4 Å Molecular Sieve  
  • PACU2F2 Sintered Pore Element Filter for >15 µm Particulates 
  • PACU2F3 13X Molecular Sieve with Desiccant

The PACU2F1, PACU2F2, and PACU2F3 filters are replacement filters for the PACU2 pure air circulator unit system. The PACU2F1 filter consists of indicating desiccant and 4 Å molecular sieve with 70 g moisture capacity for air- and gas-drying. The PACU2F2 filter is a sintered pore element filter that removes particulates larger than 15 µm with better than 95% efficiency. The PACU2F3 filter consists of a 13X molecular sieve and indicating desiccant, which traps volatile organic compounds. If the filters are saturated, the airflow will be reduced as indicated by the flow meter.

The indicating desiccants of the PACU2F1 and PACU2F3 filters will change color from blue to pink when saturated with water. Filter saturation can be checked by opening the drawer of the PACU2 unit and checking the viewing window on the filter housing. After several months of use the desiccant filter is likely to need replacement. Additionally, the desiccant and molecular sieve can be regenerated by heating the materials. Installation and filter regeneration instructions for the desiccant filter can be found in the PACU2 unit manual.

• Low-Outgassing Tubing for PACU2 Pure Air Circulator Unit
• 0.18" ID x 1/4" OD (4.6 mm ID x 6.4 mm OD), 1 MPa @ 20 °C Tubing
• Continuous Operation Temperature: -4 °F to 392 °F (-20 °C to 200 °C)
• Available in 13.1' (4 m) and 26.2' (8 m) Lengths

This clear low-outgassing tubing is required for supplying and returning air or inert gas (N₂) to the pure air circulator unit. This tubing is resistant to abrasions and many commonly used chemicals, and can be used in any application where maintaining high purity is critical. It has a max pressure rating of 1 MPa at 20 °C and is available in both 13.1' (Item # PACU2T4) and 26.2' (Item # PACU2T8) lengths. The PACU2 system includes the PACU2T4 Tubing. Even though the tubing can handle air temperatures from -4 °F to 392 °F (-20 °C to 200 °C), the PACU2 unit is rated for air temperatures from 41 °F to 104 °F (5 °C to 40 °C).

Note: Only low-outgassing semi-flexible or rigid tubing is compatible with the PACU2 system, other tubings such as the HPU6 hose are not suitable for use with the air purifier.

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Pink, Water-Saturated Desiccant in the Former PACU System

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Blue, Unused Desiccant in the Former PACU System

• Desiccant Air- and Gas-Drying Filter
• Filter Set Includes a 15 µm In-Line Particle Filter and a 13X Molecular Sieve
• Direct Replacement Filters for the Former PACU Pure Air Circulator Unit

The PACU-FTR1 filter is a desiccant air- and gas-drying replacement filter for the former PACU Pure Air Circulator Unit system. This filter will change color from blue to pink when saturated with water. As shown to the right, the vent holes on the top of the unit offer a convenient way to check for saturation without having to disassemble the unit. After several months of use the desiccant filter is likely to need replacement. Installation instructions for the desiccant filter can be found in the former PACU unit manual.

The PACU-FTR2 and PACU-FTR3 are fine filter replacement sets for the former PACU Pure Air Ciculator Unit. The first filter in each set is a 15 µm in-line particle filter, which removes particulates with better than 95% efficiency. The second is a 13X molecular sieve, which traps volatile organic compounds. If the filters are saturated, the airflow will be reduced as indicated by the flow meter. When replacement is needed, both filters should be replaced simultaneously. Step-by-step installation instructions for these filters can be found in the PACU manual.

The 13X molecular sieve comes in two different styles. When the filter set needs to be replaced, it should be replaced with the set that contains the same style of sieve. For PACU systems purchased before September 1, 2015, please purchase the PACU-FTR2 Replacement Filter Set. For PACU systems purchased on or after September 1, 2015, please purchase the PACU-FTR3 Replacement Filter Set.