23 Capacity Test 2 Error MP4000

Description

Capacity Test 2 Error 

• Occurs during pretrip (PTI) test only. 
• When the supply air temperature does not reach 0 °C (32 F) within preset time. 
• Indicates: 
• Incorrect location of supply air sensor. 
• Air leakage at supply sensor cable. 
• Defective supply air sensor. 
• Interchanged sensor connections. 
• Incorrect evaporator fan rotation or high speed operation. 
• Incorrect refrigeration system operation. 
• Container/side panels defective, damaged or leaking. 
• Air exchange vent open too much. 
• Low refrigerant charge. 
• Cooling circuit defective. 

Corrective Action 

• Enter Manual Function Test and start evaporator fans on high speed and let operate fans for 5 minutes. Check supply, return and evaporator coil (defrost) sensor temperatures. Sensor readings should be the same (supply air may be 0.5 °C [1.0 F] higher due to fan motor heat). 
• Open evaporator door and inspect evaporator fan rotation. Make sure fans are rotating correctly on low and high speed. 
• Check the sensor connections. 
• Enter Manual Function Test menu. Start and check current draw of the following components separately and together: compressor, vapor on, condenser fan and evaporator fans (high). Check discharge and suction pressure readings. Also check the refrigerant charge.