- 5 -
- 4 -
To check the humidifier’s operation, note the Control setting and set the
Automatic Humidifier Control to the test mode when the furnace blower
motor is operating. Water will flow into the humidifier for 1 minute and
then it will turn off. This insures the humidifier is operating properly. Do
not leave the Control in the test mode as it will not operate. Reset the
Control to it’s original setting.
TABLE 3 – Outdoor-Indoor Relative Humidity
Model *HUMD200ABM00B with Manual Humidifier Control
or Model *HUMD300ABA00B and *HUMD500APA00B with
Automatic Humidifier Control in Manual Mode:
(for Automatic Humidifier Control – see page 3)
The Manual Humidifier Control is installed either in the living area (typically
near the thermostat) or in the cold air return. The Automatic Humidifier
Control (in the Manual Mode) is installed in the cold air return. It is important
to anticipate a drop in outdoor temperature and reduce the setting
accordingly to avoid excessive condensation. For example, with an outdoor
temperature of 20°F the recommended setting will be 35% relative humidity.
If the temperature is expected to fall to 0°F that evening, then merely reduce
the setting to 25% several hours prior to the temperature change.
The recommended settings on the Humidifier Control are based on years of
research (see Table 3) and experience as to what is best for the average
home. These settings represent a compromise between RH levels that would
be most desirable for comfort reasons and humidity levels that are suitable
for protection of your home. For example, a wintertime indoor RH of 50%
may be considered ideal by some, but unfortunately, it probably would result
in damage to your home. Observance of the recommended RH levels on your
Humidifier Control, therefore, is an important safeguard. Condensation of
water on inside windows in the form of fogging or frost is usually an
indication of too high relative humidities. This same condensation can take
place in other areas in your home with the possibility of damage resulting.
Outside Temperature
Recommended RH
+40°F
45%
+30°F
40%
+20°F
35%
+10°F
30%
0°F
25%
– 10°F
20%
– 20°F
15%
The Humidifier Control is a precision instrument that can be used to
determine the RH accurately in your home during the winter. Turn the dial
to the lower setting, then reverse the dial direction slowly until a “click”
is heard. At this point, read the RH on the dial. This will be very close to
the actual RH in your home.
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)
D
ia
l
S
et
ti
ng
TABLE 2 – % Relative Humidity Guide
