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TABLE 1 – Operation Guide
Models EHUMD300ABA00B and EHUMD500APA00C with Automatic
Humidifier Control:
(for Manual Humidifier Control – see page 5)
Your Automatic Humidifier Control is installed in the cold air return. During
the first heating season, your Automatic Humidifier Control needs to be
set initially to match your home’s condition. Please follow these steps
when adjusting your Control (refer to Figure A).
1. Turn the dial setting knob to “5,” which is within the normal range.
During the next 24-48 hours it may be necessary to adjust the dial for
more or less humidity, depending on your personal comfort and home’s
requirements. Refer to the “Operation Guide” (Table 1).
2. During the coldest portion of the first heating season, minor
adjustments may be necessary. This is dependent upon your individual
home construction, refer to the “Operation Guide” (Table 1).
Condition
Solution
Condensation on windows
Reduce the setting on the control dial
by 1 increment.
Lack of humidity
Increase the setting on the control dial
by 1 increment.
Humidifier does not operate
Turn dial to “Test.” Make certain furnace
and blower are operating. If humidifier
still doesn’t operate, consult your air
conditioning and heating dealer.
Humidifier won’t shut off
Turn dial to “Off.” If humidifier continues
to operate, consult your air conditioning
and heating dealer.
Test mode
System operation is checked by setting
the knob to “Test.” Make certain furnace
and blower are operating. Humidifier will
operate for one minute.
The relative humidity in your home
will now be accurately controlled
to meet your needs and should not
need further adjustment during
future heating seasons. Make note
of the dial setting in the event you
temporarily move the knob when
performing annual maintenance of
the Humidifier.
OPERATING INSTRUCTIONS
FIGURE A
90-1054
Your Automatic Humidifier, is a high precision system that will accurately
maintain the relative humidity in your home. For every 1°F change in
outdoor temperature, the Control will automatically adjust the indoor
relative humidity (RH) by
1
/
2
%. If you would like to determine the RH in
your home, follow these steps:
1. Determine the outdoor temperature.
2. Activate the furnace blower by setting your thermostat fan switch to the
“On” position, or setting your thermostat to a higher temperature.
3. Turn the Humidifier Control dial setting to the “Off” position. Then, slowly
turn the dial clockwise until you hear the solenoid valve “click on.” Next,
slowly turn the dial counter clockwise until you hear the solenoid valve
“click off.” At this point, make note of the dial setting.
4. Locate your dial setting on Table 2. Follow the dial setting to the right
until it intersects with the current outdoor temperature. This is the
relative humidity in your home under existing conditions.
5. Return the thermostat and the Humidifier Control to their original
settings.
The Automatic Humidifier will accurately control the humidity in your
home to a maximum of 45% RH and a minimum of 10% RH. The values of
outdoor temperature and dial settings may fall in between or outside of
the listed values in Table 2. In these cases, you can only approximate your
home’s actual indoor RH.
As an example, if the outdoor temperature is 20°F, and, following step 3,
the humidifier turns off at “5” on the dial range, then the RH in your home is 35%.
-10
0
10
20
30
40
1
10 10 10 15 20 25
2
10 10 15 20 25 30
3
10 15 20 25 30 35
4
15 20 25 30 35 40
5
20 25 30
35
40 45
6
25 30 35 40 45 45
7
30 35 40 45 45 45
Outdoor Temperature (°F)
Dial Setting
TABLE 2 – % Relative Humidity Guide