All 3 types of installations can be used in the attic (Stand Alone, Central Draw Point or Return-Return). The example shown below is a
Return-Return installation (connection to a forced air system).
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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 cross-contamination and achieve the highest efficiencies, the f
orced air system blower must always be ON. See figure below.
NOTE: Home with multiple forced air systems should have 1 unit on each system.
Do not connect the HEPA 4000 to any forced air system supply duct.
CAUTION
Due to the potential temperature difference between the attic and the rest of the house, all unit ducts must be insulated.
CAUTION
The attic temperature must always be above 0°C (32°F).
CAUTION
1. TYPICAL INSTALLATIONS (CONT’D)
1.2 INSTALLATION FOR HEPA 4000 ONLY (CONT’D)
1.2.2 HEPA 4000 ATTIC INSTALLATION