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Model 1042LH Humidifier Installation Manual
7. Connect drain hose to 5/8" spout on humidifier cabinet
using hose clamp provided. Run 5/8" hose to suitable
drain such as floor drain, laundry sink or to a condensate
pump (sold separately). Be sure hose has continuous
slope and is not kinked at any point.
8 Turn on water supply and check operation of humidifier.
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 flow of water through
distributor trough and evaporator pad. The standard
990-37-76 (GFI #7008) orifice will supply approximately
3.5 GPH of water at a line water pressure of 60 PSI. For
low water pressures (20-40 PSI) a larger orifice 990-37-75
(GFI #7009) is available to provide the same flow. Leave
humidistat set at the recommended setting.
Installation Final Steps
How The Humidifier Works
• The operating principle of the humidifier is based on the most efficient and economical means of
evaporating water to the air. The humidifier uses only 2.5 watts of electrical power during operation, less
than the smallest household light bulb. The heat necessary for evaporating water is produced by the
furnace. The water supply to the humidifier is controlled by the electric solenoid valve. The humidistat
connected in series with the solenoid provides low voltage control of the humidifier. The humidistat is
designed for wall mounting in the living area or surface mounting on the return air duct.
• Water flows through a strainer, is metered through an orifice to provide the proper amount of water, and is
supplied to the Vapor Pad
®
by the distributor trough. Approximately 200
CFM of air is by-passed from the warm air plenum through the humidifier
and returned to the cold air plenum. Moisture is evaporated to the air
passing through the evaporator pad.
• Minerals are not blown into the air stream as occurs in atomizing
humidifiers; they are left on the evaporator pad where a high percentage
is carried off with the waste water.
• When the humidifier is installed and operating, no adjustments are
necessary other than setting the control knob on the humidistat to the
desired level of humidification. Set knob on the humidifier to "OPEN"
position. To turn the humidifier off, close the water supply valve, switch
electrical power off and turn the humidistat off. If furnace is used for
summer cooling or ventilating set air damper on "CLOSED".
•
CAUTION
:
Do not set relative humidity too high during cold weather. Excessive humidity may cause
condensation on windows or in walls. Refer to recommended settings as described in the humidistat
owners manual.
At Outside
Temperature
Recommended
Setting
-20°F
-29°C
15%
-10°F
-23°C
20%
0°F
-18°F
25%
+10°F -12°C
30%
+20°F
-7°C
35%
+30°F
-1°C
40%
!
