How to Repair Your Truck Refrigeration Units by Yourself?

2016-05-31


Catalog 

  • Foreword
  • Chart 1: truck refrigeration units problems for self-checking and repair manual
  • Chart 2: truck refrigeration units common problems for repair manual
  • Chart 3: Fault Code and solutions
  • Conclusion


Foreword to Guchen’s Truck Refrigeration Units Repair


This truck refrigeration units repair manual is suitable for standard model. Information of some option items might not be included in this manual, which you need to consult our technical service department of the company.
 

 

Truck Refrigeration Units Common Problems & Solutions to These Common Problems

 
Here is a chart for you to check out your truck refrigeration units why not refrigerating or why refrigerating not enough.

You can check it by yourself, and you can also contact us for truck refrigeration units repair manual or change the truck refrigeration units’ spare parts for a great working performance.

truck refrigeration units spare parts
PHOTO: truck refrigeration units spare parts

 

Problems

Possible Reasons


Truck Refrigeration Units Repair Manual                                         

 

      Truck
      Refrigeration
      Units
      Not
      Refrigerating

   Evaporator fans working

Condenser fan not work, compressors work                 

 

Check out whether the fans contact fall off or not, fans whether damage or not and ground wire whether working or not.

 

Both condenser fans and compressors not working
 

 

Check out temperature detect switch (TDS) whether damage or not, electric relay whether pull in or not, and its contact whether loose.
 

Condenser fans working, compressors not working
 


Check out clutch whether damage or not, connector lug whether fall off, belt whether loose

 

  Evaporator
fans not  working

 

Both condenser fans and compressors working

 

Check out whether speed-control switch working or not, fan lines whether break or not, and blower ground lines whether damage or not.
 

Both condenser fans and compressors not working
 


Check out whether the fuse blows out or not, and whether the electric relay working or not.
 

 Compressors working

Evaporator fans and condenser fans working

 

Fill too much refrigerant, check it whether meet the standard amounts with high and low pressure controller

 

 

Not using truck reefer units for a long time, and check whether it still has refrigerant or not.
 

    Truck
    Refrigeration
    Units
    Refrigerating
    Not
    Enough
 

                           Compressors    working


Evaporator fans,condenser fans working; evaporators and condensers working
 

 

Liquid receiver inlet and outlet connect inversely.
Check out the expansion valve whether blocked by ice or filth, and change liquid receiver.
 


Fans and other parts all working

 

Check whether condenser surface blocked by filth.

Chart 1: truck refrigeration units problems for self-checking and repair manual



 Problems 

Reasons

Self-checking

At the beginning, it refrigerates well, but after a while using refrigerating effect decline; the high and low pressure data is lower.


Driving reefer trucks on the bumpy roads, because of the shocking frequently, resulting in wire contacts loose, and refrigerant leakage.

 


Using leakage meter check out where the leaking place is, screw down loose contacts and fill in refrigerant.   
 


The truck reefer system not refrigerating; blowing hot air from blower outlet; expansion valve outlet and inlet blowing air same temperature; low presser controller shows lower number reading.
 


Using improperly.
Expansion value temperature wrap damages, valve bore closed, and resulting in refrigerant leakage.
 

Change expansion value, refill in refrigerant.

Outlet air not cooling and compressor temperature increasing; the pointer in low pressure controller downs quickly nearly to “0 “and high pressure reading more increasing.

Expansion value filter screen is blocked by mess, and it frosts in expansion value or the expansion value “sweats”.



If the blocking is not serious, start off freezing system at intervals can clear the mess.
Or take away the expansion value, use alcohol cleaning it, empty refrigerant and refill refrigerant again. 
 


 Refrigerating not enough, foresting in evaporator; both high and low pressure reading are lower. 
 

Expansion value orifice has no effect. 


Empty refrigerant, change expansion value and refill refrigerant.
 


 After few days working of the units, refrigerating is declining gradually, high pressure controller reading higher and low pressure controller reading lower.  
 

Drying agent in reservoir is saturate; expansion throttle is blocked by ice.


Empty refrigerant, change expansion value and refill refrigerant.
 

Start off the freezing system, only has air flowing but cold air, and high and low pressure controller no reading. 

TDS poor contact or compressor electromagnetic clutch wire damages.


Use the multi-meter check out the TDS whether damage or not; change the compressor electromagnetic clutch.
 

Chart 2: truck refrigeration units common problems for repair manual


Item

Fault Code

  Diagram Display

Solutions

Inner temp. sensor


Inner temp. sensor open

circuit: P1-H
 
Inner temp. sensor

short-circuit: P1-L
 

 



 

  Refrigeration mode when set temperature
 
   is under 0℃ and vice versa.

   Fault code flashes every 1 sec.

Defrost temp. sensor

Defrost temp. sensor open

circuit:P2-H

Defrost temp. sensor

short-circuit: P2-L

 

 


Defrosting according to defrost temperature

shut down.

Fault code and inner temperature alternate

display every 1 sec.
 

Refrigerant

line pressure

High pressure fault:HP

Low pressure fault:LP

 


All shut down.

Fault code and inner temperature alternate

display every 1sec.
 

Power voltage

Under DC 19V / DC10V : LUEr

Over DC 32V / DC16V: HUEr

 


 


All shut down.

Fault code and inner temperature alternate

display every 1sec.
 

Temp. abnormal alarm

High Temp Alarm: HA

Low Temp Alarm:LA

 

  

 

No variation in output.

Stand-by

 

Stand-by model cannot

detect AC power:

NOSP

 


  All shut down. Fault Code. If want use

ROAD OPERATION,

must restart the controller.

 

Chart 3: truck refrigeration units fault code and solutions


truck reefer units control panel

PHOTO: Fault code displays in Control Panel


Conclusion

Guchen’s Truck refrigeration units supplied by our company are guaranteed with long-term, trouble free running as long as you operate and maintain them in correct way.

Make sure to use spare parts provided by Zhengzhou Guchen Industry Co.,Ltd. for maintenance to assure best quality and reliability.

GUCHEN Industry is constantly striving to improve performance of its products to meet request of customers.

* The information contained in this truck refrigeration unit’s manual is subject to change without notice

* For the more convenient reading, please download our PDF Truck Refrigeration Units Repair Manual on the page left top.