Page 4 of 5
507390-01
Issue 1733
Air Filter
All indoor return air must be filtered before it passes through
the evaporator coil. A permanent-type filter is furnished
with the unit, located directly in front of evaporator coil.
Removing the front panel permits access to the filter.
The filter should be cleaned at least once during each of
the heating and cooling seasons and more frequently if
unusual dusty conditions are encountered. To clean the
permanent filter, shake the filter to remove excess dirt
and/or use a vacuum cleaner. Wash the filter in soap or
detergent water and re-install after filter is dry.
The filter supplied need not be oiled after washing.
If an installation is made in which it is more desirable to
mount the filter exterior to the unit, in the return duct work
or otherwise, the permanent filter supplied can be used
or a disposable filter may be used. If a disposable filter is
used, the minimum area required is as shown in Table 1.
Table 1. Minimum Required Surface Area for
Disposable Filters
Cooling Chassis Model
Number
Filter Area
(sq. in.)
EWC 12
300
EWC 18
480
EWC 24
480
EWC 30
480
Ductwork
Provide ductwork sufficiently large to handle the larger
of the air volumes for heating or cooling provided by this
model.
Connect supply duct to top of unit using canvas connection
or other flexible connection to prevent noise transmission
into the duct system.
To connect the return duct to the unit, use a straight piece
of duct 22” wide by 6” deep.
Insert the duct into the opening in the bottom of the unit
and flange the duct over the existing flanges around the
opening inside the unit. Make sure that all sides of the duct
are flanged over to permit removal of the cooling chassis if
required. Use a flexible connection to attach the remainder
of the return ductwork.
Operation
Operation of this unit is automatic and will provide heating
or cooling depending on the setting of the thermostat.
Heating
1. Turn on the main power supply.
2. Set the thermostat system switch to “HEAT”.
3. Set the thermostat heating scale to the temperature
desired.
Cooling
1. Set the thermostat system to “COOL”.
2. Set the thermostat cooling scale to the temperature
desired.
Blower Operation
Continuous operation of the air handling blower will be
obtained if the thermostat fan switch is set to “ON”.
With the thermostat switch set to “AUTO”, the air handling
blower will cycle corresponding with the thermostat cycling.
To Shut Down Unit
For temporary or short periods of shutdown, set the
thermostat system switch to “OFF”. For a prolonged period
of shutdown, set the thermostat system switch to “OFF”
and turn off the electrical power supply.
Blower
The unit contains a direct drive, multi-speed blower motor.
The proper speed has been set at the factory. Refer to the
wiring diagram on the unit for proper wiring connections.
Adjustments
No adjustments are required or should be attempted
regarding any of the components of the cooling chassis
and electric heating section.
The unit should be checked to see that none of the wiring is
loose or missing. The plug-in electrical connector between
the cooling chassis and the main control compartment
should be checked to make sure that the plug is firmly
seated and none of the wires are loose.
