System Characteristics
Chapter 6 Page 1
NOTE: This section is still being written, and one more section will be added for R600.
Lets Talk Steps to Troubleshooting a Refrigerator No-Cool
Customer calls and says their refrigerator stopped cooling and needs service. Below are the steps which you should use to begin troubleshooting in a suggested order. Some steps may seem basic but as a rule you should do each one. **NOTE some steps may vary based on your observations below is one scenario.
Step 1 - Before You Go
Questions to ask customer before going.
A. Brand, Make, Model, Serial, Error Codes - If you have access to technical information research, model and serial for Wiring Diagrams, Service manual, any service flashes.
B. When did they notice it stopped/ refrigerator dead, or running and not cooling - having an idea of when it stopped if it was gradual or just overnight is helpful.
C. Is either section cooling and how well - Note freezer could still be cold but not freezing so precise questions help with preparation before service.
Step 2 - Check Refrigerator Section
A. Open refrigerator a notice what food is in there, take temperature measurement, look for moisture around cabinet where door gaskets meet.
B. Single evaporator system - check damper for air flow, moisture or frost build up on damper, is damper mechanical or electrical "is it open"
C. Dual evaporator system - check refrigerator evaporator cover moisture or frost build up, refrigerator fan running -
D. System in cooling or defrost
Taking a temperature Reading with an Infrared Thermometer
Once the door is opened the air inside the refrigerator will spill out like water onto the floor. Test the walls and shelves with you hand to see if it feels cold and when using an infrared thermometer there are a few things that needs to be done to get an accurate measurement. NOTE: A copy of the instructions of use of the thermometer shown.
1. This is an infrared thermometer with a laser pointer - The laser is only there to help with aiming the meter.
2. Notice the image on the right - first the laser pointer about 3/4" above what is actually being tested.
3. When making a temperature test on average a technician is usually from 3' to 5' "Feet" away from the back wall of the refrigerator from 3 feet away the object being measure is about 3.6 inches around ' that is almost the size of a dryer vent and at 5 feet away it is 6 inches in diameter. This is important if the wall or space within that area it will affect the temperatures accuracy. This surface should be all the same material and flat/even to assure most accurate reading.
Accuracy -
1. This thermometer will read from -22 degrees Fahrenheit to 752 degrees Fahrenheit.
2.
From -22 to 0 degrees the thermometer can read 4 degrees higher of lower from the actual temperature.
From 0 to 32 degrees the thermometer can read 5 degrees higher of lower from the actual temperature.
From 32 to 752 degrees the thermometer can read 5 degrees higher of lower from the actual temperature.
NOTE: These instructions are for the Milwalkee infrared thermometer and accuracy may be different read all instructions before use.
Step 2 - Check Freezer Section
A. Open freezer a notice what food is in there, take temperature measurement, look for frost or moisture around cabinet where door gaskets meet.
B. Check Evaporator fan motor is running and moving air
C. Observe evaporator cover frost or Ice Build up