For HVAC Installer Only • Installation Guide
7
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. Maintenance
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
defrost control.
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.
Exhaust
Air
Fresh air
Inlet hood
Indoor air
return
EARD6
Motorized
damper
W8150
Controller
Figure 4: Install with no forced air HVAC system.
6. Wiring Diagrams
Dehumidistat
DH90
24VAC for powered
Humidistat
H
u
m
id
it
y
C
o
n
t
r
ol
R
é
g
u
l
a
t
e
u
r
d
'h
u
mi
d
i
t
é
-
2
0
F
-
10
F
0
F
+
10
F
+
20
F
O
v
e
r
2
0
F
15
%
2
0
%
2
5
%
3
0
%
3
5
%
4
0
%
H
U
M
I
D
I
T
Y
S
E
T
T
IN
G
O
U
T
D
O
O
R
T
E
M
P
E
R
A
T
U
R
E
-
3
0
C
-
25
C
-
20
C
-
1
0
C
-
5
C
O
ve
r
0
C
White
Red
Yellow
Blue
Green
M23402
Figure 5: Dehumidistat only—No fresh air ventilation.
Dehumidistat
DH90
24vac for
Powered
Humidistat
Hu
m
i
d
i
ty
c
o
n
tr
ol
Ré
g
u
l
at
e
u
r
d
'h
u
m
i
d
i
té
-
20
f
-
10
f
0
f
+1
0
f
+2
0
f
o
v
e
r
2
0
f
15
%
20%
25
%
30
%
3
5%
4
0%
H
u
m
id
it
y
S
e
t
t
in
g
O
ut
d
o
o
r
T
e
m
p
e
r
a
t
u
r
e
-
3
0
c
-
25
c
-
20
c
-
10
c
-
5
c
o
v
e
r
0
c
White
Red
Yellow
Blue
Green
M23403
W8150A
Ventilation
Override
Switch
Ventilation damper
Damper
Remote
XFMR
R
C
DAMPERAUXREMOTE
Figure 6: Dehumidistat including fresh air ventilation.