
© 2014 Pentair Equipment Protection
89056284
- 10 -
TEMPERATURE CONTROL
The electromechanical thermostat is factory preset to 75 F/24 C. To change the temperature setting, remove
the nylon plug (if applicable) from the back face of the unit. Use a standard screwdriver to adjust thermostat.
For cooler temperatures turn clockwise, for warmer temperatures turn counterclockwise. The set point of the
thermostat equals the off temperature. The on temperature is 10 F/5 C above the set point.
UNITS WITH HEAT
The heating thermostat is factory preset to 55 F/13 C. The set point for the heating thermostat equals the on
temperature. The off temperature is 10 F/5 C above the set point.
PRINCIPLES OF OPERATION
If electrical power to the air conditioner is interrupted and reapplied immediately, (within 3 to 5 seconds), the
compressor may not restart due to the high back pressure of the compressor. It takes a minimum of one (1)
minute after shut-down for the compressor suction and discharge pressures to equalize in order for the air
conditioner to restart.
Operating the air conditioner below the minimum ambient temperature or above the maximum ambient
temperatures indicated on the nameplate voids all warranties.
It is recommended that the warranty section of this manual be read in order to familiarize yourself with
parameters of restricted operation.
The moisture that the enclosure air can contain is limited. If moisture flows from the drain tube continuously this
can only mean that ambient air is entering the enclosure. Be aware that frequent opening of the enclosure’s door
admits humid air, which the air conditioner must then dehumidify.
MAINTENANCE
COMPRESSOR
The compressor requires no maintenance. It is hermetically sealed, properly lubricated at the factory and should
provide years of satisfactory operating service.
Should the refrigerant charge be lost, recharging ports (access fittings) on the suction and discharge sides of the
compressor are provided for recharging and/or checking suction and discharge pressures.
Under no circumstances should the access fitting covers be loosened, removed or tampered with.
Breaking of seals on compressor access fittings during warranty period will void warranty on hermetic system.
Recharging ports are provided for the ease and convenience of reputable refrigeration repair service personnel
for recharging the air conditioner.
INLET AIR FILTER
Proper maintenance of the inlet air filter, located behind the front cover, will assure normal operation of the air
conditioner. If filter maintenance is delayed or ignored, the maximum ambient temperatures under which the unit
is designed to operate will be decreased.
If the compressor’s operating temperature increases above designed conditions due to a dirty or clogged filter
(or plugged condenser coil), the air conditioner’s compressor will stop operating due to actuation of the thermal
overload cut-out switch located on the compressor housing. As soon as the compressor temperature has dropped
to within the switch’s cut-in setting, the compressor will restart automatically. However the above condition will
continue to take place until the filter or coil has been cleaned. It is recommended that power to the air conditioner
be interrupted intentionally when abnormally high compressor operating temperature causes automatic shut-
down of the unit. The above described shut-down is symptomatic of a clogged or dirty filter, thus causing a
reduction in cooling air flow across the surface of the compressor and condenser coil.
Do not run the air conditioner for extended periods of time with the filter removed. Particles of dust, lint, etc., can
plug the fins of the condenser coil which will give the same reaction as a plugged filter. The condenser coil is not
visible through the filter opening, so protect it with a filter.
Continued operation under the above conditions can and will damage and shorten compressor life. The air
conditioner is available with an easily removable inlet filter to facilitate necessary cleaning. There should be no
reason to neglect this necessary maintenance.