Aprilaire 350 Owner's Manual page 4

The minerals and solid residue not trapped by the replaceable Water Panel
evaporator are flushed down the drain in the Models 350, 360, 500, 600 and
700. This is the most effective and least expensive method to dispose of
trouble-causing minerals. The drain also eliminates the problems caused by
stagnant water.
There are some homes where drain facilities are not accessible or available.
For these situations, or where high water hardness is not a problem, the
newest Aprilaire, Model 400, is designed to satisfy these applications.
Trouble-free performance and minimum maintenance are assured by the
design features of the Aprilaire Humidifier. All humidifier housing parts that
come in contact with water are non-metal and will never rust or corrode.
Neither heat nor water will affect them under normal operating conditions.
The Water Panel ® evaporator, designed especially for uniform, high
evaporation, and the Scale Control Insert (which encases the Water Panel)
efficiently traps mineral deposits which are often the cause of damage to
working parts in ordinary humidifiers. When properly maintained, no "white
dust" will be distributed through the living quarters. The Water Panel
evaporator is the heart of the humidifier and must be in good
condition to assure high capacity trouble-free performance. It
should be changed at least annually with the exception of the
Model 400 which should be changed twice per heating season.
Older design water distribution trays have a granular coating in the bottom of
the distribution tray to provide even water flow to each of the openings and
over the Water Panel evaporator. Do not clean the mineral scale off the
bottom of the water distribution tray at the end of the humidification
season. If the granular coating is removed, it is not necessary to purchase a
new distribution tray, simply apply a small amount of liquid dishwashing soap
over the entire inside surface of the water distribution tray. This will allow the
water to flow evenly to the Water Panel, provided the humidifier is mounted
level in order to achieve maximum capacity.
The current distribution tray incorporates a synthetic fabric liner that
replaces the granular coating and is designed to deliver water uniformly
over the entire top surface of the Water Panel evaporator, provided the
humidifier is mounted level. It is normal for some mineral deposits to form
in the distribution tray as it dries out between humidification cycles. These
deposits can actually help distribute water in the tray, but if they block the
openings, they should be removed as described in the "Periodic
Preventative Maintenance" section of this manual.
There are many humidifiers on the market. They all add moisture... with
varying degrees of efficiency. None, however, offer the features, design,
and performance incorporated into your new Aprilaire Humidifier.
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