Aprilaire 8570, Safety And Installation Instructions Manual

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6. BLOWER EXTENSION FOR HUMIDITY CONTROL
If the heating equipment has not run long enough to allow the
humidifier to meet the humidity demand, the thermostat will
continue the blower after a heat call. One second before the
thermostat turns off the heating terminal(s), the fan terminal
will be energized thus extending blower operation. If the fan
terminal was on as part of the heat call it will remain on, if it
was not on it will be turned on. The thermostat will operate
the blower for no less than 5 minutes after the heat call and
not more than 15 minutes. This will allow the humidifier to
continue to put moisture in the air to satisfy the humidity
demand. This feature can be enabled or disabled and can only
be used when an AHC is part of the installation.
Note: To take full advantage of this feature, the humidifier
should be plumbed to hot water.
To enable blower extension:
1. Make sure the thermostat is in the OFF mode.
2. Press and hold both the and buttons for 3 seconds.
– The display will show the ADV. SETTINGS MENU.
3. Use the or button to highlight “BLOWER EXTENSION”
and press the SELECT button.
4. To cancel , press the BACK button
5. To change whether Blower Extension is enabled (on) or
disabled (off), press the or button to highlight either
ON or OFF.
6. To finish and return to the ADV. SETTINGS MENU, press
the SELECT button.
Important: When the thermostat is installed as part of a
Model 6504 Intelligent Zone System, leave this feature
disabled. The Model 6504 performs this function.