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The best way to troubleshoot a warm fridge is to pay attention to its symptoms. For example, when the refrigerator and its lights turn on but the compartments aren’t cooling down, you know the problem has nothing to do with its power supply.
Check that the fridge isn’t in Demo Mode, which disables the cooling system. Then, ensure that the temperature settings are correct, as high settings could prevent cooling from ever starting. A faulty thermostat and compressor start relay could also be to blame. The thermostat will mistakenly keep the cooling system off because it thinks it’s cold, and the burnt-out start relay won’t power the compressor.
You can solve this problem quickly by taking a step-by-step approach to troubleshooting. That’s what you’ll learn to do by reading through this guide.
Why Is My Samsung Fridge Not Cooling, But The Light Is On?
Suppose your fridge is warm even though its lights turn on and the display is illuminated. In that case, that means the appliance is receiving incoming power. That will save you the effort of having to test for power supply issues.
It also helps you narrow the root cause to a handful of likely reasons.
Follow this step-by-step troubleshooting process to find out why your fridge is warm even though the lights are on:
Step 1: Disable Demo Mode
Here’s something that most people don’t realize: all refrigerators have something called the Demo Mode. This is the mode that shop owners activate on their fridges, so the lights work when customers inspect the unit.
That’s also why the mode is known as Shop Mode, Cooling Off Mode, and Exhibition Mode, depending on who you ask.
Regardless of the name, Demo Mode disables the appliance’s cooling system because it’s unnecessary for that purpose.
If your fridge isn’t cooling, but the lights are on, there’s a likelihood that the Demo Mode is enabled. You might have accidentally enabled it, or the fridge was left in that mode when it was recently shipped to your home.
You’ll know your refrigerator is in Demo Mode when the display shows “0 FF” or “oF oF” codes on the display.
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What you can do: Suppose the root cause of your problem is that the Demo Mode is turned on. In that case, all you have to do is disable it.
The precise steps to disable Demo Mode will differ depending on your fridge model. So, your best reference is the Owner’s Manual which provides instructions specific to your unit.
Typically, Demo Mode is disabled by pressing and holding a combination of buttons on the control panel until you hear a chime. As mentioned before, that combination differs depending on what model you own.
Read: 5 Reasons Why Samsung Fridge Not Cooling + Service Manual + DIY Heater
Step 2: Set Correct Temperature
Whether or not the Demo Mode was enabled, the next thing you must do is ensure that you’ve set the correct temperature on your refrigerator. The fridge will not begin cooling if you’ve previously set a temperature that was far too high.
When you adjust the appliance’s temperature to something lower than its current settings, you’ll hear and feel the refrigerator start to cool. You hear the gentle humming noise and vibrations from the compressor turning on and the fans starting to spin.
What you can do: Firstly, you’ll want to confirm that the refrigerator’s cooling system is working correctly. You can set the refrigerator and freezer compartments to the lowest temperatures possible.
Once you confirm that the refrigerator is cooling, you can rest assured that its systems are working correctly. You can set the appliance to a more reasonable temperature to protect your food items.
According to the US Food and Drug Administration (FDA), your fridge should be set at or below 40° F, while the freezer is set at 0° F. Those temperatures will ensure your fridge stores your food items safely and for as long as possible.
Read: Why Samsung Fridge Is Making “JackHammer” Noise?
Step 3: Test Refrigerator’s Thermostat
The lack of cooling could also be due to a faulty thermostat. The thermostat is designed to continuously sense the temperatures inside your refrigerator. Then, it’ll send data to the main control board (i.e. the fridge’s computer), which will determine how much cooling is necessary.
When the fridge is too warm, the thermostat will trigger the refrigerator to begin cooling. But when the appliance reaches your set temperature, the thermostat ensures that the cooling system slows down or shuts off until it’s needed again.
A faulty thermostat will not behave the way it’s supposed to. In this case, it’s not triggering the compressor and other components to begin cooling the refrigerator. As a result, the fridge stays on, but it never cools down.
What you can do: Firstly, you must confirm whether the thermostat is faulty. Unless there are visible signs of damage or a short circuit, you’ll need a
If it no longer has any continuity, that means the thermostat is no longer functioning. Replacing it with a working thermostat will fix the problem.
Read: 3 Ways To Fix Samsung Fridge Not Cooling After Power Outage
Step 4: Check Compressor Relay
You should inspect the compressor only when Steps 1-3 fail to solve the problem. The compressor is the heart of your refrigerator’s cooling system. As the name suggests, it compresses the coolant and circulates it throughout the system so the fridge can cool down.
However, the compressor relies on a small electrical component called the start relay. A relay is an electrically powered switch. So when the fridge wants to begin the cooling process, it triggers the relay, which allows power to flow to the compressor.
However, it won’t start the compressor if the relay is faulty or burned out. That will leave the refrigerator warm inside even though it has power and the lights are on.
What you can do: Compressor start relays aren’t repairable, so your only option is to replace them. However, it’s best to check the part before you decide to get rid of it.
Firstly, do the rattle test. The relay should make no sound when you shake it, but if you hear rattling, it’s damaged.
Secondly, check for any burn smells. Those smells suggest the compressor has burnt out and no longer works.
Read: 5 Reasons Why Samsung Fridge Evaporator Fan Is Not Working
Final Thoughts
When the lights in your fridge can turn on, but it doesn’t cool, you can skip troubleshooting the power supply. Instead, start by checking that the refrigerator isn’t in Demo Mode and ensure that the temperature settings are low enough.
Once you’ve ruled out those two possibilities, check the thermostat and compressor start relay. These two parts will prevent the fridge from cooling if they’re faulty or burned out. However, replacing them as soon as possible will get your fridge cool again.
