Heatcraft Refrigeration Products H-IM-79B - Manual (Page 19)

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ERROR INDICATOR LED
At initial power up, each Beacon board checks for system errors. The system error check
involves checking the various temperature sensors to determine whether any of these
sensors are shorted or open.
The system will pumpdown and cycle off and will not restart until the fault is cleared or
the circuit breaker reset, for the following conditions:
- Suction sensor shorted, open or not installed
- Room temperature sensor shorted or not installed
- Pressure Transducer open or not installed
The system will pumpdown, cycle off and try to restart for three consecutive times . Each
try will be after the 4 minutes “Hold Off” period, for the following fault conditions:
- Superheat too low
- High pressure or low pressure cutout
- Oil pressure
After the third try, the system will shut down and not try to restart. The Alarm contacts will
be closed and an alarm message displayed on the LED.
ERROR CODES
E1 - Room temperature sensor shorted, open or not installed
E2 - Defrost temperature sensor shorted, open or not installed
E3 - Suction temperature sensor shorted, open or not installed
E4 - Suction pressure transducer shorted, open or not installed
E5 - Outdoor temperature sensor shorted
E6 - Low superheat
E7 - Compressor shut down (high or low pressure switch open or oil pressure
switch open)
E9 - Multi-in/multi-out wiring error
EVAPORATOR FANS SHUT OFF
In some installations, it is desirable to shut off the evaporator fans periodically. This is easily
accomplished on Beacon II by wiring a single pole, single throw switch (SPST) between the
terminals marked “SERVICE” and “COM” on the Beacon II board. Closing this switch will
cause the system to pumpdown and shut off. Air Defrost fan motors must be wired through
the fan relay on the Beacon II board for this to be effective on Air Defrost systems. The
entire system will be shut off and remain off until the SPST switch is opened.
Air Defrost evaporator fans are setup to run constantly. If there is a need to shut down the
evaporator fans on an Air Defrost system, this can be accomplished by wiring the
evaporator fan motor or evaporator fan motor contactor through the fan relay on the
Beacon II board. When this is done and the Air Defrost system is placed in “SERVICE,” the
evaporator fans will shut off when the system is in pumpdown.
Error Indicator