Northwind MAC1211 Engineering, Installation And Service Manual page 7

CONDENSATE PUMP
Condensate pump in unit models
MAC1211/1811
CONDENSATE ALERT LIGHT, RED
Every NorthWind unit is equipped with a red Condensate Alert light. The light is lit when one of two conditions ex-
ists: 1) The condensate tank is full. 2) The condensate cannot be pumped out of the condensate pump. 3) This requires
pushing the reset button in the unit's cord storage compartment (MAC1211/1811) or behind the front access door
(MAC60/90), to restart the unit.
POWER READY LIGHT, GREEN
All NorthWind units are equipped with a green "Power Ready" light. When lit, it indicates there is power at the recepta-
cle. Even when the unit is in the "off" position, the light should be lit. If this light is "off", there is no power available
for the unit to run. Perhaps a fuse or circuit breaker should then be checked.
THERMOSTAT
Every NorthWind unit is equipped with an electromechanical thermostat operating on 24 volts. The dial on the unit
control panel is in the off position when turned full counterclockwise. When turned full clockwise, the temperature
setpoint will be approx. 55° F @ ± 4°. The temperature sensing function is through a remote bulb located in front of
the evaporator coil, in the air stream.
CONDENSATE PUMP TRANSFORMER
Used only on 480 volt 3 phase models, it provides 230 volts to power the unit's condensate pump.
CONTROL TRANSFORMER
The control transformer supplies 24 volts to the unit's low voltage control system. It is a foot mounted, 40VA, multi-
tap primary that is energized when the power cord is connected to a "hot" receptacle.
EVAPORATOR FAN RELAY/CONTACTOR
The evaporator fan relay controls the 2 speeds of the evaporator motor on models MAC1211/1811. The relay is SPDT
with a 24 volt coil. Models MAC60/90 use a separate contactor for each speed using 24 volt coils.
TIME DELAY RELAY
Each unit is equipped with an adjustable, low voltage time delay relay to protect the compressor from short cycling,
which could cause internal damage. This device is "delay on break" actuated and is located in the electrical box on the
lower back panel of the unit. The adjustment dial on the relay is factory set and should not need any further attention.
Every NorthWind unit is provided with a condensate pump. The pump has a 20
foot lift, an internal check valve, and a safety float switch. The pump is securely
mounted to the base pan with all primary wiring and piping factory finished. A con-
densate discharge line is required when the pump is being used. When not used, the
pump is simply in standby mode.
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