What does a defrost thermostat do?

The defrost thermostat, also known as a defrost bimetal, is a safety device that monitors the temperature of the evaporator coils. When the coils drop to a specific cold temperature, it closes a circuit, allowing the defrost heater to activate and melt frost. It then opens the circuit when a higher temperature is reached, preventing overheating.

How can I test a defrost thermostat?

A defrost thermostat can often be tested for continuity using a multimeter. The thermostat should show continuity when it is below its activation temperature (e.g., frozen) and open when it is above. Always refer to your appliance's service manual for specific testing procedures and temperature ranges.

Is a defrost thermostat the same as a thermistor?

No, they are different. A defrost thermostat is a bimetal switch that opens or closes a circuit based on a fixed temperature. A thermistor is a temperature-sensitive resistor that changes its resistance based on temperature, sending variable signals to the control board.

Refrigerator Defrost Thermostat Replacement Guide

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🏆 RECOMMENDED PART

RecDec 2 Pack Refrigerator Defrost Temp Sensor Replacement Temperature Thermostat Probe for Samsung Fridge Units DA32-00006W RF217ACRS

Package: 2x Temperature Sensor
Fast Repairsave Your Time & Money
Compatible with:RS2533VK/XAA,RB215BSSB/XAA-00,RT21M6215SG/AA-00,RS2534BB/XAA,RB1944SL/XAA,RB2155SH/XAA,RS2666SL/XAA,RS2623WW/XAA,RB2055SW/XAA,RS2530BWP/XAA-00,RF217ACPN/XAA-00,RS2530BBP/XAA-00,RS2623VQ/XAA,RB1955SH/XA...
This is a manufacturer substitution. Part may differ in appearance but is a functional equivalent to prior parts including; DA32-00006C,DA32-00006G,DA32-00006L,DA32-00006M,DA32-00006U,DA32-00006B,DA32-00006D,DA32-10105P
Unplug the Refrigerator and Safely Store Any Food That Could Deteriorate While the Power Is off Before Installing This Part

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What the DA32-00006W does

The defrost thermostat monitors the temperature of the evaporator coils, signaling the defrost heater to activate when temperatures drop below a set point. It prevents excessive frost buildup by ensuring timely defrost cycles.

Symptoms when this part fails

Excessive frost buildup in the freezer
Refrigerator not cooling properly
Water pooling inside or outside the fridge
Defrost heater not activating
Food spoilage due to fluctuating temperatures

Compatibility

Fits the Bosch family. Specifically:

Any unit originally equipped with OEM part number(s): RS2533VK.
Check the model/rating plate inside your appliance and compare it against the fitment table on the product listing before ordering — this guide does not list specific compatible models because Amazon does not provide verified fitment data through this pipeline.

Also replaces: RS2533VK

Tools you'll need

Screwdriver set
Wire strippers
Multimeter
Pliers
Nut driver

Difficulty: Moderate · Time: 45-90 minutes

How to install the DA32-00006W, step by step

Unplug the refrigerator from its power source.
Access the freezer compartment and remove interior panels to expose the evaporator coil.
Locate the defrost thermostat clipped to the evaporator coil.
Disconnect the electrical wires and remove the old thermostat.
Connect the new thermostat, ensuring secure wire connections.
Reinstall the interior panels and secure them.
Plug the refrigerator back in and test its operation.

Related troubleshooting

If swapping this part doesn't fix the issue, check these next:

What is Refrigerator Defrost Mode and How it Works