6
Model 1137 Humidifier Installation Manual
Breathe Healthier! Residential Whole House Indoor Air Quality
FIG. 6B WITH WITH CONSTANT POWER TO HUMIDIFIER
Use with mechanical humidistat only. Mount a junction
box and 115 volt grounded outlet. Connect the on-off
switch in series with the hot or black wire. Install a field
supplied 24 volt relay and attach to HUM and C on the
furnace control board. Install humidistat and connect one
side to one yellow wire on humidifier. Connect the other
side of the humidistat to one end of switch side of the
relay. Connect the other switch side of the relay to the
remaining yellow wire on humidifier.
CAUTION: Red humidifier leads are not used
for this wiring method. Do not touch red wires
together. Damage to the humidifier will result.
6.
!
!
AC L
AC N
HUM
SNSR
L1
(HOT)
L2
115v.
60CY.
HUMIDIFIER CONTROL LEADS
(YELLOW WIRES)
FAN CONTROL
ON-OFF
SWITCH
SINGLE SPEED
BLOWER MOTOR
ACC
EAC
(HOT)
C
115v.
60CY.
ON-OFF
SWITCH
6A
6C
6B
GRD
HUMIDIFIER
120v. OUTLET
HUMIDIFIER
COMMON LEAD
120v. OUTLET
C
HI
LO
GA50 CURRENT
SENSING RELAY
MULTI
SPEED
BLOWER
MOTOR
6D
12500 AIR
PRESSURE
SWITCH
NO
C
L1
(HOT)
L2
115v.
60CY.
ON-OFF
SWITCH
GRD
HUMIDIFIER
120v. OUTLET
L1
(HOT)
L2
115v.
60CY.
ON-OFF
SWITCH
GRD
HUMIDIFIER
120v. OUTLET
GRD
FIG. 6A WITH FURNACE CIRCUIT BOARD
On furnaces with output terminals ACC, or EAC
check output voltage to determine that termi-
nals are 115V. Connect on-off switch in series
with the hot wire.
WARNING: CHECK WITH LOCAL AUTHORITIES FOR COMPLIANCE.
WARNING: ALL WIRING SHOULD COMPLY WITH LOCAL ELECTRICAL CODES.
FIG. 6C AIR PRESSURE SWITCH WITH TWO
SPEED BLOWER MOTOR
On furnaces with a two speed blower, the
humidifier and a Model 12500 Air Pressure
Switch may be wired from a continuous 115
volt power source. Install the on/off switch
and Air Pressure Switch in series with the hot
or black wire. The Air Pressure Switch will
detect furnace operation and supply power to
the humidifier accordingly.
CIRCUIT DESCRIPTION
The humidifier is connected to the 120 volt AC circuit through a control relay. The secondary coil of an
isolation transformer, a diode and resistor supply 24 volts DC for the control circuit which also includes the
humidistat and relay coil. When the control circuit is completed by the humidistat, the relay closes, supplying
120 volts to the fan motor and 24 volts to the solenoid valve.
FIG. 6D CURRENT SENSING RELAY WITH TWO-SPEED
BLOWER MOTOR
On furnaces with a two speed blower, the humidifier
may be wired from a continuous 115 volt power source.
Install the on/off switch in series with the hot or black
wire. Install the GA50 (GFI #7026) Current Sensing Relay
in series with the humidistat circuit. The Current Sensing
Relay will detect furnace operation and supply power to
the humidifier accordingly.
Installing / Wiring Your Control Cont.
6 B
(HOT)
C
115v.
60CY.
ON-OFF
SWITCH
HUMIDIFIER
120v. OUTLET
GRD
L1
YELLOW WIRES
FROM HUMIDIFIER
FURNACE
CONTROL BOARD
60CY.
24V.
C
HUM
FIELD SUPPLIED
RELAY 24V COIL, N.O.
HUMIDISTAT
C
NO
NC
6B
