Acrs (Advanced Condensate Removal System) - Northwind MAC1211 Engineering, Installation And Service Manual

CONSTANT PRESSURE EXPANSION VALVE /FREEZE STAT/HOT GAS BYPASS
Each NorthWind unit is provided with a constant pressure expansion valve, freeze stat or hot gas bypass to prevent
frost formation on the evaporator coil. This is most useful when operating in high humidity conditions at low fan
speeds and moderate to lower temperatures.
HIGH PRESSURE SAFETY SWITCH
ADVANCED CONDENSATE REMOVAL SYSTEM
The unit's evaporator blower will continue operation at its selected mode. To resume cooling operation, the tank must be
emptied. An adjustment screw, located behind the tank, can vary the cut-off switch. If a lighter weight (less water) is de-
sired, turn the adjusting screw clockwise. Do not exceed 1 full turn counterclockwise.
WATER LEVEL MICROSWITCH
The water level microswitch turns off the
compressor and condenser blower when the
tank needs to be emptied. As condensate col-
lects in the tank, it becomes heavier. When
the spring pressure is exceeded by the weight
of the tank, the adjusting screw lowers the
lever on the switch, closing the circuit to the "condensate alert" light
and opening the circuit to the compressor and condenser blower. This
switch operates on 24 volts.
Spring and tray attachment
Water level adjustment screw and locknut
Microswitch mounted in unit
STANDARD FEATURES continued
Each NorthWind unit is equipped with a manual reset high pressure switch
to protect the refrigeration system and compressor. The cut-out pressure for
all models is 425 PSIG. If the system exceeds this pressure, the compressor
will stop. When the system pressure drops to 300 PSIG or less, the reset
button can be pushed to restart the compressor. THE RESET BUTTON IS
LOCATED IN THE CORD STORAGE COMPARTMENT on models
MAC1211/1811. The button is located behind the front service door on
models MAC60 and MAC90. This protects the button from damage during
transport and setup. The high pressure switch capillary line is attached to a
schrader access valve on the liquid line. This allows replacement of a de-
fective switch without recovering the refrigerant.
All 1, 1½, and 3 ton units are supplied with the Advanced Condensate Removal System. This
system includes a 5 gallon tank and a high lift condensate pump. The user can choose be-
tween the tank or pump with no wiring or electrical changes. Simply attach a short piece of
1/2 inch o.d. tubing (included with unit) from the evaporator drain pan outlet fitting and in-
sert the other end into the inlet opening on the condensate pump. This system is located be-
hind the door on the lower front panel of the unit. If the pump is used, the pump discharge
line must run to a drain. If the tank is used, the water level control system shuts off the com-
pressor and turns on the red "condensate alert" light when about 5/8 full.
Evaporator pan outlet
1/2 inch o.d.
Condensate pump
water inlet
6
VIEW LOOKING THROUGH DOOR
WITH TANK REMOVED