Troubleshooting

Section 4

Troubleshooting

4.1Alarms

Alarm display is an independent controller software function. If an operating parameter is outside of the expected range or a component does not return a valid signal back to the controller, an alarm is generated. The EverFRESH® Controlled Atmosphere option alarms are AL907, AL909, AL910, AL929, AL962, AL976, AL977, AL978, AL979, AL980, and AL981. For units configured with the CO2Injection option, additional alarms AL982 and AL983 may be generated.

4.2Alarm Code Descriptions

AL907 Manual Fresh Air Vent Open

Cause:

For units equipped with EverFRESH and a vent position sensor (VPS), the controller will monitor the manual fresh air opening at a pre-determined time. If during this time the fresh air vent is open and EverFRESH is active, an alarm will be generated. If an alarm is active, the controller monitors the manual fresh air once per hour. Upon clearing the alarm, the controller goes back to monitoring at the pre-determined time.

Component:

Vent Position Sensor (VPS)

Troubleshooting:

Manually re-position the vent to 0% and confirm using Cd45. If Cd45 is not reading 0%, perform a calibration of the panel. If unable to obtain a zero reading, replace the defective VPS. If the unit is loaded, ensure the vent is closed. Note and replace the VPS on the next PTI. The alarm will not affect the EverFRESH system from operating.

AL909 Oxygen Sensor (O2) Fault

Cause:

Triggered anytime the O2 sensor reading is outside of the normal operation range, after an initial signal was detected.

Action:

EverFRESH Air Compressor (EAC) 100% duty cycle and open the EverFRESH Air Valve (EA). This will prevent low O2 and cargo loss. If both AL909 and AL910 are active, run the EAC and open the EA.

Component:

O2 Sensor, O2 Amplifier

Troubleshooting:

Check Cd44 and scroll down to 02V. The O2 sensor output will be displayed in millivolts (130mV to 4100mV is a good range). Check wiring (see schematic) and check for bad connections or wires improperly positioned.

If O2 sensor is available, remove the upper fresh air panel and evaporator motor and replace the sensor. If after replacing the sensor Cd44 reads outside of the normal range and AL909 continues, replace the amplifier.

If parts are not available, turn the EverFRESH option off via Cd71 and open the manual fresh air vent.

AL910 Carbon Dioxide Sensor (CO2) Fault

Cause:

Triggered anytime the CO2 sensor reading is outside of the normal operation range, after an initial signal was detected.

Action:

EverFRESH Air Compressor (EAC) 100% duty cycle and open the EverFRESH Air Valve (EA). Will prevent low O2 and cargo loss. If both AL909 and AL910 are active, run the EAC and open the EA.

Component:

CO2 Sensor

Troubleshooting:

Check wiring (see schematic) and check for bad connections or wires improperly positioned.

Check the voltage on the back of MD connectors pin MD09 (-) and MD03 (+12 VDC) with the controller energized. If 12 VDC is not available, check the controller. If 12 VDC is available, check the back of pin MD02 for a voltage between 1.0 - 4.7 VDC. If not present, replace the sensor.

If part is available, remove the upper fresh air panel and evaporator motor and replace the sensor. If no part is available, take no action and service at next PTI.

AL929 Loss of Atmospheric Control

Cause:

Triggered whenever the CO2 level is above its setpoint by 2%. Or, when the O2 level is below its setpoint for longer than 30 minutes. The alarm is triggered off when the levels return to within the normal range.

Action:

Enable Alarm LED. Open the fresh air vent and verify the air compressor is enabled.

Verify all EverFRESH components are functioning properly by checking for EverFRESH alarms and running a P-20 PreTrip. If a component is not functioning properly, it will fail the appropriate P-20 sub test. Note components in order below.

Component:

Membrane Pressure Transducer (MPT)

Troubleshooting:

Remove the MPT. Turn on the container unit. Using Cd44, verify the MPT pressure reads between -5 and +5 psig. Outside this range or if AL977 active, replace the sensor.

Component:

EverFRESH Air Compressor (EAC)

Troubleshooting:

Verify EAC fuses FEF1, FEF2 & FEF3.

Check P20 results for a failure mode:

•Possible detected failure with EAC current consumption, check compressor motor windings, and verify voltage on all 3 phases.

•MPT failure. Follow steps above.

•Failure of AC contactor for EAC. Ohm contactor coil and check resistance across contactor legs, with power removed.

Component:

EverFRESH Air Valve (EA)

Troubleshooting:

A closed or plugged EA solenoid could prevent fresh air from entering the container. P20-2 tests the valve. Potential failure results:

•MPT pressure fails to change when the valve is energized. Check for blockage in the valve or piping.

•EA current is not correct. Access function code Cd74 and perform a ML5 self-check to verify the controller is functioning properly. If it passes, perform a ohm check on the back of CA08 pin and TRX2 (ground) using the carrier service tool (part # 22-50485-00).

Component:

Water Drain Valve (WDV)

Troubleshooting:

A closed or plugged WDV or filter housing could prevent any air from entering the container. P20-3 tests valve operation. Potential failure results:

•MPT pressure fails to change when the valve is energized. Check for signs of blockage by removing the WDV housing and particulate filter housings. Clean any debris. While removed, inspect the WDV and associated piping for blockage.

•EA current is not correct. Access function code Cd74 and perform a ML5 self-check to verify the controller is functioning properly. If it fails, replace the controller. If it passes self-check, replace the WDV.

Component:

EverFRESH Nitrogen Valve (EN)

Troubleshooting:

An open or leaky EN valve would allow N2 to go into the sensor sensing chamber causing an inaccurate reading. P20-5 tests this valve. Potential failure results:

•If tests fail, remove the EN and verify the valve is not clogged or damaged.

•EA current is not correct. Access function code Cd74 and perform an ML5 self-check to verify the controller is functioning properly. If it fails, replace the controller. If it passes self-check, replace the EN.

AL962 Oxygen (O2) Out of Range

Cause:

This is a notification alarm and does not pose a risk to fresh produce, however the benefit of atmosphere control will not be lost. O2 level reaches pulldown limit and then O2exceeds 5% over setpoint for 30 minutes.

Component:

Upper Fresh Air Panel

Troubleshooting:

Verify the upper fresh air panel has not been opened.

Component:

EverFRESH Air Valve (EA)

Troubleshooting:

An EA that is stuck open can allow continuous flow of fresh air into the container when the compressor is on. See troubleshooting in the AL929 section.

Component:

Container Air Tightness

Troubleshooting:

Seal container where possible (access panels, rear doors, mounting hardware, etc).

AL976 Air Compressor Internal Protector Open

Cause:

EverFRESH Air Compressor (EAC) internal protector opens.

Component:

EverFRESH Air Compressor (EAC)

Troubleshooting:

Follow steps defined in AL929 EAC testing.

Component:

ML5 Controller

Troubleshooting:

Access function code Cd74 to perform an ML5 self-diagnostic test.

AL977 Membrane Pressure Transducer (MPT) Fault

Cause:

The EverFRESH Air Compressor (EAC) is running and pressure is not within the range of -5 to 200 psig. Or, the EAC has been OFF for five minutes and pressure is not within the range of -5 to 5 psig.

Component:

Membrane Pressure Transducer (MPT)

Troubleshooting:

With the EverFRESH system off for 15 minutes, bring up function code Cd44 and scroll to "EF Pt". Verify that the value is between -5 psig and 5 psig. A "- - - - " value indicates a failed sensor or harness. Pressure outside of range indicates a bad sensor, replace the sensor if bad.

Component:

ML5 Controller

Troubleshooting:

Access function code Cd74 to perform an ML5 self-diagnostic test.

AL978 Air Compressor Pressure Low

Cause:

EverFRESH Air Compressor (EAC) engaged and Fresh Air Vent (FAV) and Water Drain Valve (WDV) are closed and compressor has been running for longer than 20 seconds and Membrane Pressure Transducer (MPT) Pressure < 75 psig.

Component:

Membrane Pressure Transducer (MPT)

Troubleshooting:

With the EverFRESH system off for 15 minutes, bring up function code Cd44 and scroll to "EF Pt". Verify that the value is between -5 and 5 psig. A "- - - - -" value indicates a failed sensor or harness. Pressure outside of range indicates a bad sensor, replace the sensor if bad.

Component:

System Plumbing

Troubleshooting:

Inspect plumbing, hoses, fittings, check valve, and orifices for signs of leakage. Repair as required. With the compressor running, spray the pressure relief valve with soapy water. Replace if leaking. If a spare pressure relief valve is not available, try opening and closing the valve with an O-ring on the valve to try and re-seat.

See the condition for membrane pressure transducer (MPT) reading low in the EverFRESH troubleshooting table, Section 4.3.

AL979 Air Compressor Pressure High

Cause:

EverFRESH Air Compressor (EAC) engaged and air pressure > 135 psig.

Component:

Membrane Pressure Transducer (MPT)

Troubleshooting:

With the EverFRESH system off for 15 minutes, bring up function code Cd44 and scroll to "EF Pt". Verify that the value is between -5 psig and 5 psig. A "- - - - -" value indicates a failed sensor or harness. Pressure outside of range indicates a bad sensor, replace the sensor.

Component:

System Plumbing

Troubleshooting:

Inspect plumbing, hoses, fittings, check valve, and orifices for signs of blockage. Repair as required.

See the condition for membrane pressure transducer (MPT) reading high in the EverFRESH troubleshooting table, Section 4.3.

AL980 Fresh Air Valve (EA) Fault

Cause:

When the system energizes the EverFRESH Air Valve (EA) solenoid and membrane pressure does not drop 40 psi, the alarm is triggered. The alarm triggers OFF when membrane pressure transducer (MPT) pressure drop is more than 40 psi when EA is opened.

Component:

EverFRESH Air Valve (EA) Solenoid

Troubleshooting:

Run a P20 test to verify mechanical and electrical performance of the solenoid. If the electrical test fails, replace the valve. If the mechanical test fails, check for obstructions blocking system flow and remove. If it still fails, replace the valve.

Component:

ML5 Controller

Troubleshooting:

Access function code Cd74 to perform an ML5 self-diagnostic test.

AL981 Water Drain Valve (WDV) Fault

Cause:

When the system energizes the water drain valve (WDV) and membrane pressure does not drop 40 psi, the alarm is triggered. The alarm triggers OFF when membrane pressure transducer (MPT) pressure drop is more than 40 psi when the EverFRESH Air Valve (EA) is opened.

Component:

Water Drain Valve (WDV)

Troubleshooting:

Inspect WDV bowl and outlet piping for obstructions, clean components.

Run a P20 test to verify mechanical and electrical performance of solenoid.

If the electrical test fails, replace the valve. If the mechanical test fails, check for obstructions blocking system flow and remove. If it still fails, replace the valve.

Component:

ML5 Controller

Troubleshooting:

Access function code Cd74 to perform an ML5 self-diagnostic test.

AL982 CO2 Injection Failure

Cause:

If unit is configured with the CO2 injection option, this alarm is triggered when Cd76 is set to “A-CO2” or “PrCON” to enable CO2 injection and CO2 < CO2 setpoint - 0.5% volume and the IPT < 20 PSIG.

Component:

CO2 Supply

Troubleshooting:

Verify CO2 supply is available and supplied at the recommended pressure.

Component:

CO2 Injection Port Schrader Valve

Troubleshooting:

If proper pressure is available at the CO2 injection supply port, verify that the Schrader valve is being depressed by the supply hose properly to allow flow.

Component:

CO2 Injection Solenoid

Troubleshooting:

Run a P20 test to evaluate the solenoid and replace if test fails.

AL983 CO2 Injection Pressure Transducer Failure

Cause:

If unit is configured with the CO2 injection option, this alarm is triggered when Cd76 is set to “A-CO2” or “PrCON” to enable CO2 injection and volts are not in the range of 0.5 to 4.95 VDC.

Component:

CO2Injection Pressure Transducer (IPT)

Troubleshooting:

From function code Cd74, run a controller self-diagnostic test. Evaluate results to see if there is a controller or transducer issue. If there is a sensor issue, or the test passes, change the transducer.

4.3EverFRESH Troubleshooting

This troubleshooting section is for the EverFRESH option only. Prior to testing the EverFRESH unit, verify that the refrigeration system is functioning properly.

Table 4–1 Troubleshooting System Conditions

Condition	Possible Causes	Recommended Actions
EverFRESH Air Compressor (EAC) Will Not Start	EAC contactor not engaging	Verify that temperature setpoint is in the correct range for EverFRESH to operate.
	EAC internal protector open	Check air compressor IP.
	Fuse F3 blown	Check fuse F3.
	EAC contactor engaging, but compressor not running	Check fuses FEF1, 2, 3.
		Check input power.
		Check motor resistance at the EAC connector.
EverFRESH Air Compressor (EAC) Running But Cycling ON / OFF	EAC shuts off every 45 minutes	Normal duty cycle.
EverFRESH Air Compressor (EAC) Running But Cycling ON / OFF	Internal motor protector	Check.
EverFRESH Air Compressor (EAC) Hums But Does Not Start	Low line voltage	Check voltage.
	Single phasing	Check power / fuses.
	Shorted or grounded motor windings	Check resistance.
	EAC seized	Check current.
Membrane Pressure Transducer (MPT) Reading Low	Dirty EAC intake filter	Replace the intake filter.
	Water separator housing / drain leaking	Remove the housing and clean debris. Verify that the WDV is closing.
	Particulate filter housing / drain leaking	Remove the housing and clean debris. Verify that the WDV is closing.
	Leaky valve	Remove the valve and attempt to remove obstruction. If this is unsuccessful, replace the valve.
	EverFRESH piping leak	Inspect piping for abrasions / cuts in piping. Verify all connections are tight. If unable to locate leak, remove the EAC discharge line and inject 80 psig of nitrogen or clean dry air into the system and check for leaks with soapy water. Ensure the unit locked out when performing this procedure.
	Air compressor defective or leaking	Perform a major / minor rebuild based on hours of operation.
Membrane Pressure Transducer (MPT) Reading High	Water separator or air filters clogged	Remove housings and clean debris, verify WDV opening.
	EverFRESH piping blocked	Inspect plumbing, hoses, fittings, check valve, and orifices for signs of blockage. Repair as required.
	Nitrogen membrane defective	Operating the system for a period of time can “dry out” the membrane and increase efficiency. Run a Pre-trip “AUTO CA” test to check membrane efficiency. Allow the system to operate for one hour and check nitrogen levels. If nitrogen percentage is increasing, continue to dry out. If not, replace the membrane.
EverFRESH Air Compressor (EAC) Runs But O2 Does Not Come Down	Fresh air vent open	Check vent, close.
	Leak in piping	Check system for leaks.
	Sensor defective	Check sensor alarms. Replace as needed.
	Nitrogen membrane defective	Run P20 test to validate nitrogen concentration.
	Container box not sealed	Perform pressure decay test.
	Leaky cylinder head	Perform minor rebuild.
EverFRESH Air Compressor (EAC) Runs But O2 Does Not Come Up	EverFRESH Air Valve (EA) does not open	Check F3 fuse.
		Run a P20 PTI test. P20-2 will check for proper valve operation: electrical and mechanical.
	Water separator not draining	Clean inspect water separator housing.
	Particulate filters not draining	Inspect / replace particulate filters.
EverFRESH Air Compressor (EAC) Runs But CO2 Does Not Come Down	Nitrogen membrane defective	PTI check. See Section 3.4
CO2 Does Not Come Up	Leaky container box	Inspect container, verify fresh air vents closed, if possible check curtain install.
CO2 Does Not Come Up	Produce not capable of raising CO2	Some produce does not generate much CO2 and needs to be pre-charged with gas. If charge leaks out can only be replaced by recharging.
In CO2 Injection Mode And Not Maintaining Setpoint	Low CO2 bottle pressure	Check bottle pressure gauge to ensure bottle delivering 50 PSIG. Verify hose from tank to CO2 injection input is depressing the Schrader valve on the inlet.
	Leaky container box	Inspect condition of the box. Verify the fresh air panel is closed. If possible, check condition of the curtain.
	CO2injection solenoid failure	Run a P20 test and check P20-6 results. Replace if necessary.
CO2Injection Pressure Transducer (IPT) Not Reading In Range	Restricted CO2input to the system	Remove CO2 source and run a P20 test. Validate the results of P20-7. If it fails, replace the sensor.