STI 18729 - Manual (Page 9)

© 2010 Pentair Technical Products 89059119 - 9 -
TEMPERATURE CONTROL
The electromechanical thermostat is factory preset to 75 F/23 C. To change the temperature setting, remove the nylon
plug from the front face of the unit. Use a standard screwdriver to adjust thermostat. For cooler temperatures turn
clockwise, for warmer temperatures turn counterclockwise. Setpoint differential is 6 F.
Units With heat
With a dial setting of 75 F, heat will turn on @ 70 F and turn off @ 75 F. Cooling will turn on @ 85 F and turn off at 80 F.
There is a 10 F difference between the heater off setpoint and cooling on setpoint to prevent both from operating at
the same time.
The dial range of the thermostat is 50-95 F.
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.
Units with the optional malfunction switch have a normally open connection between the red & yellow wires and
normally closed with the red and blue wires. During alarm the red and yellow wires will be closed and the blue and red
wires will be open.
Maximum electrical ratings for the switch are 13A for 120 VAC and 10A for 240 VAC.