Manual Mode - Aprilaire 350 Safety & Operating Instructions Manual

MANUAL MODE

FIGURE B – Manual Mode
When installed in the Manual Mode (see Figure B – internal switch in
"MAN" position and "M" in the display), 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 correct
setting will be 35% RH. If the temperature is expected to fall to 0°F, then merely
reduce the setting to 25% several hours prior to the temperature change.
See Table 1 for the recommended settings. These settings, which are
based on years of research, represent a compromise between RH levels that
would be most desirable for comfort and humidity levels that are suitable
for protection of your home and to avoid condensation on your windows.
For example, a wintertime indoor RH of 50% may be considered ideal for
comfort, but unfortunately, it probably would result in condensation, which can
cause damage to your home. Observing the recommended RH levels on your
Humidifier Control is an important safeguard. Condensation of water on the
inside surface of windows in the form of fogging or frost is usually an indication
of too much humidity. This same condensation can occur in other areas in your
home, possibly resulting in damage.
TABLE 1 – Outdoor Temperature/ Indoor Relative Humidity
Outside Temperature
+40°F
+30°F
+20°F
+10°F
0°F
–10°F
–20°F
Recommended RH
45%
40%
35%
30%
25%
20%
15%
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WATER PANEL CHANGE INDICATOR
The control keeps track of humidifier operation time. The yellow "Change
Water Panel" light flashes after a preset amount of running time has
elapsed. This running time is preset by the installer based on the humidifier
model and water hardness.
Refer to the Annual Maintenance section for instructions on changing the
Water Panel or call your heating and air conditioning dealer for service.
After the Water Panel is replaced, turn the Control knob to the "Test/Reset"
position until the green "Humidifier ON" light flashes, to reset the Water
Panel change timer.
TEST/RESET
The Test/Reset feature allows the humidifier operation to be checked even if
90-1236B
there is no call for humidity. See "Check the Humidifier Operation" on page 9.
ADDITIONAL INFORMATION
Your humidifier is a precision system that will accurately maintain the RH
in your home. For every 2°F change in outdoor temperature, the Digital
Humidifier Control will automatically adjust the indoor RH by 1%.
The Digital Humidifier Control will accurately control the humidity in your
home to a maximum of 45% RH.
The RH Values in Table 2 are targets based on outdoor temperature and the
Digital Humidifier Control setting. The actual RH may vary due to conditions
in the home (cooking, showering, etc.).
TABLE 2 – % Relative Humidity Guide
Outdoor Temperature (°F)
-10°F 0°F 10°F 20°F
1 10% 10% 10% 15%
2 10% 10% 15% 20%
3
10% 15% 20% 25%
4 15% 20% 25% 30%
5 20% 25% 30% 35%
6
25% 30% 35% 40%
7 30% 35% 40% 45%
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30°F 40°F
20% 25%
25% 30%
30% 35%
35% 40%
40% 45%
45% 45%
45% 45%