Aprilaire 220 - Manual (Page 3)

Your
Aprílaire'
Humidifier
I. PRINCIPLE OF OPERATION
With your purchase of a humidification system, you have
invested in a humidifier that operates on the evaporative
principle - nature’s own way of adding moisture - and will
provide the proper relative humidity all during the heating
season. It is very possible that you have questions concerning
your new humidifier - questions on what it can do for you, and
what you should do to receive maximum benefits from it This
booklet is intended to help you do exactly that.
Nature, in producing an invigorating comfortable April day,
combines just the right temperature and the right amount of
moisture. Aprilaire Humidifiers employ the same principle, with
refinements, to give you the proper relative humidity for maxi­
mum allowable comfort all winter long.
The important considerations in the evaluation of a humidifier
are Positive Control, Sufficient Capacity, Trouble-free
Performance and Minimum Maintenance. The operating
principle of your Aprilaire provides all of these advantages.
Here, briefly, is the method:
The Aprilaire Humidifier (except the Models 350 and 360) is
installed to operate in conjunction with the furnace blower
motor. When the humidistat or Automatic Humidifier Control
calls for humidity and the blower motor is operating, water flows
to the distribution pan located at the top of the unit. The water is
uniformly distributed across the width of the pan and through a
scientifically designed system of outlets. It flows by gravity over
the Water Panel* evaporator, the heart of the unit. Dry, hot air is
moved through the moisture-laden Water Panel evaporator
where the evaporation takes place. The now humidified air
carrying moisture in vapor form (nature’s own way) is circulated
throughout the home.
The Models 350 and 360 use service hot water (140T maxi­
mum) for its heat source, as heat is needed for evaporation.
While the water going to the unit is hot, the flushing water to the
drain will be cold. The heat is extracted during the evaporation
process.
The correct water flow is determined by an orifice
equipped with each drain type unit V№en the unit is op^ting,
there will be a small, steady stream of water to drain, which
flushes away most of the trouble-causing minerals. Do not
use the saddle valve to regulate the water flow. It is designed to
be completely opened or closed. The minerals and solid residue
-1 -