Status
This fault is a low pressure event. If the event occurs within the same call 3 times, the system will switch from an Alert to an Alarm and lock the unit out for 4 hours.
Description
The pressure detected in the suction line is below the acceptable minimum.
Cause
Often this is caused by a system that is undercharged but it can also be caused by poor evaporator airflow, low load, or a restriction in the system.
Solution
Check refrigerant charge - compare pressure readings to published values for the unit at the current ambient temp. Adjust refrigerant charge level as necessary.