16
Troubleshooting
Service Manual
Serene HB80/110
6
Troubleshooting
Diagnostic Table
Complaint
Possible Cause
Repair
1. Cabinet not
operating
• Loss of power supply
• Check power supply
2. Cabinet light
not operating
• Loss of power supply
• Check power supply
• Failed fluorescent or LED
lamp
• Check lights and ballasts
3. Compressor
will not start
• Loss of power supply
• Check power supply
• Overload protector tripped • Replace overload
• The temperature controller
knob is in the off (‘0’)
position.
• Adjust temperature
controller.
4. Compressor
starts too
frequent, with
operation time
too long
• Short of refrigerant
• Fix leak and add charge
• Over-charge of refrigerant • Remove refrigerant to
correct charge
• Temperature controller not
reading temperature
correctly
• Check air temperature with
thermometer. Adjust offset
if required
• Faulty temperature
controller
• Replace controller
• Dirty condenser coil
• Clean condenser coil.
• Cabinet overloaded with
product
• Reduce product loading
• Ambient temperature too
high
• Ensure maximum
operating conditions are
40°C at 75% RH
• Drying filter is blocked
• Replace filter
5. Compressor
runs without
stopping and
temperature
inside cabinet
is too low
• The temperature controller
is set too cold
• Adjust temperature
controller to a warmer
setting
• Faulty temperature
controller
• Replace temperature
controller
• The temperature sensing
probe of the controller is
incorrectly positioned
• Reposition temperature
controller probe.
6. Compressor
starts and runs,
but short
cycles on
overload
protector
• Supply voltage too high
• Check voltage
• Compressor too hot
• Check refrigerant charge
and unit ventilation
• Faulty overload protector
• Replace overload
• Faulty starting relay
• Replace starting relay
• Short circuit in compressor • Replace compressor
