
6
Model 1099LHS Humidier Installation Manual
Breathe Healthier! Residential Whole House Indoor Air Quality
!
Installing / Wiring the Control
7D
7. Connect drain hose to 1/2" spout on humidier cabinet using hose
clamp if necessary. Run 1/2" hose to suitable drain such as oor
drain, sewer or laundry sink.
CAUTION: Be sure hose has continuous slope and is not kinked at
any point.
8. Turn on water supply and check operation of humidier. Set humidistat
to a demand setting. With the furnace off, the solenoid valve should
be closed. Start the furnace, the solenoid valve should open when
the blower or burner circuit is energized. Check ow of water through
distributor trough and evaporator pad. The standard Orange orice
GA4299 (GFI #7581) will supply approximately 4.75 GPH of water at
a line water pressure of 60 psi. For low water pressures (20-40 psi) a
larger Blue orice GA4232 (GFI #7587) is available to provide the same
ow. Leave humidistat set at the recommended setting.
WIRE JUMPER
7D
(HOT)
115v.
60CY.
ON-OFF SWITCH
COMMON LEAD
FURNACE
C
HI
LO
GA50
CURRENT
SENSING
RELAY
MULTI
SPEED
BLOWER
MOTOR
AC L
AC N
HUM
SNSR
24V. SOLENOID VALVE
727-58 24 V. TRANSFORMER
(HOT)
C
115v.
60CY.
ON-OFF SWITCH
AC L
AC N
HUM
SNSR
24V. SOLENOID VALVE
727-58 24 V. TRANSFORMER
L1
CNO
(HOT)
L2 115v.
60CY.
ON-OFF SWITCH
12500 AIR
PRESSURE SWITCH
AC L
AC N
HUM
SNSR
24V. SOLENOID VALVE
727-58 24 V. TRANSFORMER
R
FURNACE
CONTROL BOARD
C24v.
60CY.
AC L
AC N
HUM
SNSR
24V. SOLENOID VALVE
FURNACE
BOARD
W
WIRE JUMPER
OUTDOOR TEMP. SENSOR
OUTDOOR TEMP. SENSOR
OUTDOOR TEMP. SENSOR
OUTDOOR TEMP. SENSOR
N
W
24v.
60CY.
WIRE
JUMPER
WIRE
JUMPER
WIRE
JUMPER
6A6A 6B
6C
!WARNING: ALL WIRING SHOULD COMPLY WITH LOCAL ELECTRICAL CODES.
Thin Gasket
Face FIG. 1
WALL MOUNT: Use
Outer & Inner Portions
DUCT MOUNT: Use
ONLY Outer Portion
Mounting
Base
Thick Gasket
DUCT MOUNT ONLY
1. Locate the humidistat at least 24" upstream of the
humidier or bypass on the return air duct. Avoid areas of
direct radiation like secondary heat exchangers in the fan
compartment.
2. Place template using level. Cut sensor hole as shown on
template. Drill four 3/32” holes (not shown).
3. Remove the housing from the base by prying with a small
screwdriver at the notch in the side of the housing.
4. Gaskets: Place the outer portion ONLY of the thin foam
gasket on the humidistat base and mount the base with four
screws. Place the thick gasket inside the wall mount base to
seal off air entering through the vents. Low voltage wire may
enter the humidistat under the foam seal.
5. Connect wires to screw terminals on the control assembly as
shown in wiring diagram. Replace housing.
6. MHX3C: DUCT Mounting (Return Air Duct)
CAUTION:Do not install the humidistat on the warm air duct.
6. MHX3C: WALL Mounting Instructions
1. Choose a location for the humidistat about ve feet
above the oor on an inside wall with average room
temperature and humidity conditions.
2. Drill a small hole in the wall and run low voltage wiring
to the location chosen. Pull about 6” of wire through the
hole. Plug the opening to prevent drafts from affecting
the humidistat operation. Remove the housing from the
base by prying with a small screwdriver at the notch in
the side of the housing.
3. Gaskets: Place the entire outer and inner portions of the
gasket on the base as shown. Do NOT install the thick
gasket inside the base.
4. Mount the base horizontally over the wires using level.
Attach directly to the wall, using four screws provided.
5. Connect wires to screw terminals on the control assembly
as shown in wiring diagram. Replace housing.
!
6D