Honeywell F50F Owner's Manual page 8

If you have a
humidifier
69-0756—2
If your system includes an atomizing humidifier,
you may want to install a standard furnace filter
between the humidifier and the air cleaner. This
filter would keep the humidifier spray's mineral
deposits from collecting on the air cleaner. This
filter should be checked regularly and changed
when it shows signs of mineral or dirt buildup. If
you do not install a filter, you will probably need
to wash the cell(s) and prefilter(s) more often to
remove the mineral buildup.
If an ultrasonic room humidifier is used often,
especially if filled with tap (undistilled) water, the
cell(s) and prefilter(s) will require more frequent
washing. A white residue will accumulate on the
cell(s) from the minerals in the water. This
residue may also contribute to "white dust"
(see p. 17).
All Honeywell whole house humidifiers may be
used in a system with the Honeywell Electronic
Air Cleaner without any additional filters or
system modification.
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