PRODUCT DESIGN
65
24 Volt Dehumidistat Wiring - Two-Stage Variable
Speed Gas Furnaces
The optional usage of a dehumidistat allows the furnace’s
circulator blower to operate at a slightly lower speed dur-
ing a combined thermostat call for cooling and dehumidistat
call for dehumidification. This lower blower speed enhances
dehumidification of the conditioned air as it passes through
the AC coil. For proper function, a dehumidistat applied to
this furnace must operate on 24 VAC and utilize a switch
which
opens on humidity
rise.
To install/connect a dehumidistat:
1. Turn OFF power to furnace.
2. Secure the dehumidistat neutral wire (typically the white
lead) to the screw terminal marked "DEHUM" on the
furnace integrated control module.
3. Secure the dehumidistat hot wire (typically the black
lead) to the screw terminal marked "R" on the furnace
integrated control module.
4. Secure the dehumidistat ground wire (typically the green
lead) to the ground screw on the furnace junction box.
NOTE
: Ground wire may not be present on all
dehumidistats.
5. Turn ON power to furnace.
To enable the dehumidify function on the circulator blower
interface board:
1. Cut the jumper wire labeled "CUT FOR DEHUM" lo-
cated adjacent to the DEHUM screw terminal.
NOTE:
(W14 imprinted on the circuit board is the "CUT
FOR DEHUM" location.)
Once the jumper wire is cut, the dehumidify function is
enabled during a
combination
call for cooling (T-Stat) and
dehumidification (Dehum-Stat). The yellow LED adjacent
to the DEHUM screw terminal will be illuminated during
dehumidification.
( 50V51 and 50V61 )
Integrated Ignition Control Module
S
INGLE
S
TAGE
T
HERMOSTAT
A
PPLICATION
W
G
Y
Single-Stage Heating with Single-Stage Cooling
R
B/C
G
R
W1
W2
O
YLO
Y
DEHUM
TWIN
Y
C
NEU
HOT
Furnace Integrated
Control Module
Thermostat
Single-Stage Heating with
Single-Stage Cooling
(
)
Remote
Condensing Unit
(Single-Stage Cooling)
Dehumidistat
[Optional]
NOTE:
To apply a single-stage heating thermostat, the
thermostat selector jumper on the integrated Control
module
must
be set on single stage.
W1
G
Y
Two-Stage Heating with Single-Stage Cooling
R
W2
B/C
G
R
W1
W2
O
YLO
Y
DEHUM
TWIN
Y
C
NEU
HOT
Furnace Integrated
Control Module
Thermostat
Two-Stage Heating
with
Single-Stage Cooling
(
)
Remote
Condensing Unit
(Single-Stage Cooling)
Dehumidistat
[Optional]
G
Y
Two-Stage Heating with Two-Stage Cooling
R
B/C
G
R
W1
W2
O
YLO
Y
DEHUM
TWIN
NEU
HOT
Furnace Integrated
Control Module
Thermostat
Two-Stage Heating
with
Two-Stage Cooling
(
)
Remote
Condensing Unit
(Two-Stage Cooling)
Dehumidistat
[Optional]
Y
C
YLO
YLO
W2
W1