Ducting To Hvac System - Basement And Attic Installations - Aprilaire 1870 Installation Instructions Manual

DUCTING TO HVAC SYSTEM – BASEMENT AND ATTIC INSTALLATIONS
The Preferred Installation is to duct the dehumidifier to pull air from and return dehumidified air to the HVAC return duct . This installation will
ensure warm, dehumidified air is thoroughly mixed with the HVAC system air before being discharged into the living space . Alternatively, the
dehumidifier can be ducted to discharge to the supply duct, but the external static pressure of the HVAC system must not exceed 0 .6"w .c .
Required Component
10" Ductwork
FIGURE 10 – Preferred Basement Installation
10" DUCT
AIR IS PULLED
FROM AND
SUPPLIED TO THE
RETURN DUCT
DEHUMIDIFIER
FIGURE 12 – Preferred Attic Installation
6" MIN.
AIR HANDLER
FILTER
10" DIA. INSULATED DUCT
BOTH SIDES
90-2024
Ducting Notes:
• Use insulated duct when the dehumidifier is located in an unconditioned space such as an attic or a garage .
• Use a minimum of 12" of flex duct at the dehumidifier inlet and outlet to prevent vibration noise transmission .
• When ducting return to return (preferred), the dehumidifier must be wired to turn on the HVAC fan when operating (see page 14) .
• When ducting return to supply, allow adequate space before the first branch duct to ensure the warm dehumidified air is thoroughly mixed
with the HVAC system air .
10
HVAC/ FURNACE
6 ft
MIN
90-2022
PLENUM BOX OR Y-FITTING
6 FT. MIN.
CONDENSATE PAN
FIGURE 11 – Alternate Basement Installation
0.6" w.c. MAX
AIR IS
PULLED FROM
RETURN DUCT
10" DUCT
FIGURE 13 – Alternate Attic Installation
PLENUM BOX
24" MIN.
10" DIA. INSULATED DUCT
BOTH SIDES
90-2025
AIR IS DISCHARGED
TO SUPPLY DUCT
HVAC /FURNACE
90-2023
0.6" w.c. MAX
PLENUM
6" MIN. 6" MIN.
AIR HANDLER
FILTER
CONDENSATE PAN