Terra Universal Product Manual
WhisperFlow® Fan Filter Units
© Copyright 2021 Terra Universal Inc. All rights reserved •Revised April 2021
Terra Universal, Inc. • TerraUniversal.com • 800 S. Raymond Ave. • Fullerton, CA 92831 • TEL: (714) 578-6000 • FAX: (714) 578-6020 6
3. Start-Up
3.1 Installation
The fan filter unit is designed to fit on top of a Terra Laminar Flow Hood or standard clean room ceiling grid. It includes 1/4-
20 thread holes on corners for guy-wire suspension. Room-side replaceable filters are packaged separately for jobsite
installation by others.
1. Remove all packaging material from the shipping box
(Figure 1).
2. Perform a thorough visual inspection to ensure no
damage has occurred during shipping. Check that
there are no visible dents or penetrations on the filter
face and grille. If damage is discovered, contact the
freight company to file a damage claim immediately.
3. Remove the pre-filter and manually rotate the fan
wheel to make sure it does not come in contact with
any stationary parts and that there are no visible
loose screws or bolts obstructing the wheel’s
rotation.
4. Verify unit is sanitary for cleanroom placement.
5. Optional: fasten the eyebolts into each corner of the
lid assembly.
6. Lift the unit into the ceiling and position onto the
ceiling grid. If the grid is not secured, fasten to an
engineered support system with chain, s-hooks and
eyehooks (usually supported with wires).
7. Confirm fan dimensions are aligned with grid
dimensions.
8. Raise the unit and secure with support system
method suspended from a structural support bracing.
a. Minimum clearance of 1 foot (including
fixtures, ducts and pipes) on all sides and
at least 2 feet of vertical clearance between
the FFU inlet and ceiling for proper air
supply.
9. Connect the 4-pin power plug to the unit, set the
speed switch to the desired position (units are
shipped from the factory with the speed switch set to medium), and turn on the external power switch. With
power applied, the fan will rotate, and filtered air will exit the HEPA filter.
Note: After completing the Initial Setup, validation may be performed by a third-party testing service for HEPA filter integrity (leak-
testing), Air Changes per Hour and particle counter measurements to verify ISO 5 particle levels. Third-party testing should take
place within the intended cleanroom or another controlled environment to ensure an accurate evaluation of its performance.
To avoid thermal overload on FFU’s with Permanent Split Capacitor (PSC) motors, do not use LOW
speed switch when the FFU is connected to a PDM.
Figure 2: Hanger Supports
