14
L-3571 ENGLISH
TROUBLESHOOTING GUIDE
Before you call for service, review this list of problems and solutions. It may save you time and expense. This list contains
common occurrences that are not a result of defective workmanship or materials. If you need service after trying these
procedures, call your dealer. Also reference the wiring diagrams in this manual.
Table 5: General Troubleshooting
PROBLEM
POSSIBLE REASON/SOLUTION
Compressor and fan (or
pump) does not run.
1.
Circuit breaker off.
Turn on or reset circuit breaker.
2.
Thermostat set incorrectly.
Check thermostat. Set for a cooler setting.
3.
High/Low pressure switch.
Check the Dometic control for fault LP or 1A. Call
technician.
Fan or pump operates but
compressor does not (high
pressure switch or thermal
overload has tripped)
1.
Low voltage to unit.
Check for low voltage to unit. Klixon may be open.
2.
Poor condenser cooling.
Check fan and coil for proper airflow. Ventilate area if
temperature is above 100°F/38°C. Check seawater
system.
3.
High/Low pressure switch.
Check the Dometic control for fault LP or 1A. Call
technician.
Compressor and fan (or
pump) running, but box does
not cool.
1.
Poor condenser cooling.
Check fan and coil for proper airflow. Ventilate area if
temperature is above 100°F/38°C. Check seawater system for proper flow.
2.
Thermostatic Expansion Valve (TXV) not set correctly.
See technician for service.
3.
Low refrigerant charge.
Check for a refrigerant leak and repair. Evacuate system
and recharge with the correct amount of R-404A.
4.
TXV Mechanical failure.
Have technician confirm diagnosis and replace.
System starts to cool, but
stops as plates freeze.
1.
Moisture in system.
Check sight glass for moisture
. Yellow indicates moisture;
green indicates dry system.
Compressor operates, but
seawater pump doesn’t.
1.
Pump relay failure.
Turn on or reset pump breaker. Check pump relay
and pump
relay trigger.
Unit does not run.
1.
Power is OFF at panel.
Turn Power ON, check to see if thermostat display comes
on.
2.
Thermostat is set incorrectly or may be faulty.
If the display is on, check for proper
thermostat setting. Ensure the correct voltage at thermostat.
If the thermostat is showing a fault code, refer to “Thermostat Display Error Messages
(digital Dometic control)” on page 15.
If thermostat still does not send voltage to the condensing unit or if fault code is
present, replace
thermostat.
3.
No voltage is getting to the thermostat, but the panel switch is on.
Check for
loose or missing wiring connections behind the control, then in electrical box. Make
sure that there is not another in-line cut-off switch.
4.
Start component failure.
Check basic electrical components for failure. Replace if
necessary. See technician.
5.
Compressor failure.
See technician.
Displays not lit.
1.
Power disconnected.
Check circuit breaker.
2.
Loose connection.
Check for loose connections.
3.
Wrong voltage.
Check voltage input of control.
4. See technician.
