ALTERNATE EXTERNAL DRY CONTACT CONTROL AS DRIVING CONTROL
When a dry contact control is used to control the first dehumidifier, Unit #1 must be set to
ENABLE EXTERNAL
in the set-up menu� All downstream
units must be set up to
ENABLE EXTERNAL
in each set-up menu� See page 12 for set up details and wire as shown in
FIGURE 13
�
SEQUENCE OF OPERATION
Each unit in the daisy chain responds to the first unit being controlled by the external control� When the humidity level rises above the humidity
setting, all units will dehumidify until the humidity measured by the external control falls below the setting�
IMPORTANT:
If the external control experiences a fault, all downstream dehumidifiers will also stop function� If any dehumidifier experiences a fault,
that unit will stop operation as determined by the fault but all other units will continue operating� If any unit loses power, all downstream units will
stop function�
+ - A B ODT
Sensor
Remote
Gh
Rf
Cf
Gs
Y
W
HV
AC
EQ
UIP
.
Fl
oa
t
Sw
itc
h
DH
DH
Vent
+ - A B ODT
Sensor
Remote
Gh
Rf
Cf
Gs
Y
W
HV
AC
EQ
UIP.
Fl
oa
t
Sw
itc
h
DH
DH
Vent
+ - A B ODT
Sensor
Remote
Gh
Rf
Cf
Gs
Y
W
HV
AC
EQ
UIP.
Fl
oa
t
Sw
itc
h
DH
DH
Vent
DEH
DEH
DEH
TO APRILAIRE 88XX SERIES CONTROL
OR OTHER EXTERNAL DRY CONTACT CONTROL
UNIT #1
SET UP FOR EXTERNAL CONTROL
UNIT #2
SET UP FOR EXTERNAL CONTROL
UNIT #3
SET UP FOR EXTERNAL CONTROL
90-2509
FIGURE 13
– WIRING WITH ALTERNATE EXTERNAL CONTROL
English
11
