2. TYPICAL INSTALLATIONS
(CONT’D)
A portion of stale air is exhausted to the outside and the rest is drawn to the unit.
Outside fresh air is blended with interior air and then filtered. This filtered air is
supplied to the return (plenum) of the forced air unit.
To avoid the cross-contamination and achieve highest efficiencies, the forced air
system blower must always be ON (or the unit efficiency will be affected).
The HEPA 2000 and HF 2.0 units need to be ON all the time, since they don’t
have motorized dampers. If these units are OFF, then the forced air unit will draw
outdoor air inside.
NOTE: Home with multiple forced air systems should have 1 unit on each system.
VH0043
- 14 -
2.3.3 R
ETURN
-
TO
-R
ETURN
I
NSTALLATION
(C
ONNECTION TO A FORCED AIR SYSTEM
)
2.3 HEPA 2000, HF 2.0, HEPA 3000, HF 3.0
AND
HEPA 4000 U
NIT
I
NSTALLATIONS
(
CONT
’
D
)
Do not connect the unit (HEPA 2000, HF2.0, HEPA 3000, HF 3.0 or HEPA 4000)
on any forced air system supply duct. Connect it only to the air return duct.
Do not install duct or duct connector directly above the forced air unit or
not less than 9’10’’ (3 m) of the plenum connection to the forced air unit, as
measured along the length of the duct.
CAUTION
