Figure 4: Install with no forced air HVAC system.
4.5 Noise Abatement
A length of 10' or more of acoustical flex ducting
on the outlet of the DH90 will reduce air noise from
the fan. A length of flexible ducting on all DH90
duct connections is recommended to reduce noise
transmitted to rigid ductwork in the structure.
5.1 Air Filter
The DH90 is equipped with a MERV 11 media
filter. This filter should be checked every three
months and replaced every six months. Operating
the unit with a dirty filter will reduce dehumidifier
capacity and efficiency and may cause the com-
pressor to cycle off and on unnecessarily on the
CAUTION: Operate the unit only with a
genuine Honeywell filter installed to assure
proper performance of the unit.
5.2 Optional Fresh Air Intake
Check and clean the screen on the outdoor fresh
air intake port seasonally. The screen may become
plugged during the seasons when there are many
particles in the outdoor air.
For HVAC Installer Only • Installation Guide
6. Wiring Diagrams
Figure 5: Dehumidistat only—No fresh air ventilation.
Figure 6: Dehumidistat including fresh air ventilation.
24VAC for powered