If the fridge section of your Bosch fridge/freezer is experiencing frost buildup on the back panel that quickly turns to water, it indicates a problem with the refrigerator's defrost system. The defrost system is responsible for preventing excessive frost buildup on the evaporator coils inside the fridge compartment. When this system malfunctions, frost accumulates and later melts, resulting in water pooling at the bottom of the fridge or leaking onto the floor.
Here are some possible reasons for this issue:
Defrost Timer or Control Board: The defrost system is controlled by either a mechanical defrost timer or an electronic control board. If this component fails, it can prevent the automatic defrost cycle from functioning correctly, leading to frost buildup.
Defrost Heater: The defrost heater is responsible for melting the frost off the evaporator coils during the defrost cycle. If the defrost heater is faulty, it won't generate enough heat to melt the frost effectively.
Defrost Thermostat: The defrost thermostat is a temperature sensor that monitors the temperature of the evaporator coils. If it malfunctions and fails to signal the defrost heater to turn on, frost can accumulate and cause the described issue.
Defrost Drain Blockage: If the defrost drain is blocked, water from the defrost cycle won't be able to drain properly and will accumulate in the fridge compartment.
Door Seals: Poorly sealing door gaskets can allow warm, humid air to enter the fridge, leading to excessive frost buildup.
To troubleshoot and address the problem, you can try the following steps:
Manual Defrost: Unplug the fridge and let it thaw completely to remove any frost buildup. This process may take a few hours or overnight. Keep the doors open to speed up the process.
Check the Defrost Timer/Control Board: If your fridge has a mechanical defrost timer, manually advance it to see if it initiates the defrost cycle. For fridges with electronic control boards, check for any error codes or anomalies that could indicate a problem.
Inspect the Defrost Heater and Thermostat: Use a multimeter to test the continuity of the defrost heater and thermostat. If either component shows no continuity, it's likely faulty and needs replacement.
Clear the Defrost Drain: Make sure the defrost drain is clear of any blockages. You can use a mixture of warm water and mild soap to flush out any debris.
Check Door Seals: Inspect the door gaskets for signs of damage or wear. Replace them if necessary to ensure a proper seal.
If you're unsure about diagnosing or fixing the issue, it's best to seek the assistance of a qualified appliance repair technician who can accurately identify the problem and perform the necessary repairs.