Data Aire gForce DX - Regular Maintenance Items; Air Filter Maintenance

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8.0 REGULAR MAINTENANCE ITEMS
Air Filters
The air filter section is an integral part of the environmental control system, designed within
the unit for easy front accessibility. An initial set of filters are factory installed in the unit. The
filters are 4-inch (100mm) deep, disposable, pleated design, extended-surface, nonwoven,
reinforced cotton fabric; supported and bonded to welded-wire grid; enclosed in cardboard
frame design rated not less than MERV 8 per ASHRAE Std. 52.2. A filter differential switch for
alarm activation is included.
Air filters should be checked on a regular basis and changed when they become dirty. This will
ensure efficient operation of the unit. Spare air filters should be kept in stock as these tend to
be a frequently replaced maintenance item. Air filters may require changing as often as monthly
dependent on room or space conditions. New installations with construction dust will quickly
clog filters requiring new filters.
The dap4™ control panel monitors the air filters status. A dirty filter alarm will be enunciated
on the controls display screen. Although the unit may display a dirty filter alarm, this should
not be relied on as the only determinant for replacing air filters. A misadjusted air filter
differential pressure switch may not give a proper indication of a clogged filter.
To check the air filter pressure differential pressure switch for proper adjustment, temporarily
cover approximately 75% of the return air opening using heavy cardboard or similar material. The
alarm should energize when 75% of the air is blocked, simulating dirty filters. If the alarm
energizes prematurely or does not energize at all, the pressure switch should be adjusted. All
side panels must remain closed when determining if an adjustment is necessary.
WARNING: Air filters that require changing can restrict airflow and create
problems such as coil icing or poor air distribution.
Fuses
Always replace fuses with those of the equivalent rating regarding 1) amperage, 2) voltage,
and 3) speed. For instance motors are inductive loads which require time delay fuses. Electric
reheat and humidifiers are resistive loads requiring fast acting fuses.
Electric Reheat
The electric reheat is a finned enclosed, sheath type, fabricated of stainless-steel core sheath
with plated fins to withstand moist conditions. The reheat is installed on the air discharge side
of the cooling coil and has three (3) stages. The reheat can maintain room dry bulb
conditions when the system is calling for dehumidification. The reheat section includes a
safety switches to protect the system from overheating. The low-watt density elements
eliminate ionization associated with open air electric resistance heating.
Heating elements do not normally require maintenance. However, they may accumulate a film
of dust or dirt when unused for extended periods of time. When energized, the burning
debris can create smoke or an unpleasant odor. To help avoid a problem, periodic cleaning is
recommended.