Refrigerators are classified into two types based on their defrost function. These two types of refrigerators are self-defrosting and manual defrosting, with most modern refrigerators being self-defrosting. Self-defrost systems are classified into two types. A usage-based defrost system, also known as an adaptive defrost system, and a time-based defrost system.
The time-based system starts the defrost cycle every day at a specific time, whereas the adaptive system only starts when the fridge needs to be defrosted. In this article, we will discuss a question I’ve heard: do all refrigerators have a defrost timer?
What is a Fridge Defrost Timer?
Before answering the question: do all refrigerators have a defrost timer? I’ll have to explain what a fridge defrost timer is.
A fridge defrosts timer is a motor-powered clock device that effectively manages frost levels in a refrigerator while maintaining a safe temperature.
Defrost timers are classified into two types. There are two types of defrost timers: constant or continuous run defrost timers, and accumulative defrost timers. When a refrigerator is plugged in, constant or continuous run defrost timers operate continuously, whereas accumulative defrost timers operate only when the refrigerator compressor is turned on.
Depending on the brand or model of the refrigerator, you can find the refrigerator defrost timer in various locations. Some common locations are the control panel or grille inside the freezer or the compressor area in the back of the fridge. It can also be found behind the fridge’s lower kick plate or, in some models, behind the fridge on the back wall.
Do All Refrigerators Have a Defrost Timer?
I’ve seen many people asking if all refrigerators on the market have a defrost timer. I’ll be answering that here.
The majority of modern refrigerators are self-defrosting, also known as auto-defrosting. A defrost timer is used by self-defrosting refrigerators with a time-based defrost system to automate this process.
A defrost timer is common in entry-level or older refrigerators, typically upright refrigerators. There are also manual defrosting refrigerators without a defrost timer. Individual defrosting of the fridge is required.
They are usually chest refrigerators, and the majority of them are horizontal. Some chest refrigerators include a defrost timer, but this is not common. Manual defrosting upright refrigerators are available, but they are uncommon.
Do Modern Refrigerators Need Defrosting?
If you want to keep frost levels relatively stable, most modern refrigerators use a timer. But do modern refrigerators need defrosting?
Yes. Modern refrigerators require defrosting, but most do so automatically via a defrost timer.
Modern refrigerators still require defrosting because the fridge keeps food cool, and frost accumulates, which, if not kept at safe levels, can become excessive and cover the evaporator coils, preventing airflow.
There are still some refrigerators that require manual defrosting. It must be done by a person whenever the ice level reaches a thickness of 14 to 12 inches.
How Do Modern Refrigerators Defrost?
A refrigerator timer, also known as a defrost timer, is a device that regulates the amount of frost in a refrigerator. It cycles on and off to allow frost to melt and prevent frost buildup in the fridge. So, how do modern refrigerators self-defrost?
Most modern refrigerators have a three-part automated defrosting system and are self-defrosting. A defrost timer, a defrost thermostat, and a defrost heater are among the components that play important roles in the defrost cycle.
A defrost heater’s purpose is to provide the heat required to melt the excess ice on the evaporator coils. The defrost thermostat monitors the heat produced by the defrost heater and indicates when the coils have returned to normal operating temperature.
A defrost timer manages and controls the frost levels in a refrigerator by alternating between defrost and cooling modes. It is accomplished by switching each mode on and off at different intervals or when frost is detected. Both modes are operational at the same time. The defrost mode is typically used once or twice per day, every 12 to 15 hours for about 25 to 45 minutes.
During the defrost cycle or mode, the compressor, also known as the fan or cooling function of the refrigerator, is turned off. Also, the defrost heater gets turned on. When the defrost heater is activated, the evaporating coils heat up, melting the frost.
The melted ice water drains from the refrigerator through a small passageway in the back and into a drip tray, usually located at the bottom. When you finish the defrost cycle, the timer switches back to cooling mode, and the defrost heater gets turned off.
Cooling mode circulates cold air throughout the refrigerator, causing condensation and ice formation, which aids in cooling.
Some refrigerators heat up the evaporator with hot gas from the condenser, melting the excess frost and defrosting the fridge. This system is commonly found in commercial models like ice cream display freezers.
What Are the Types of Defrost Timers?
Modern refrigerators use different defrost timers: constant, continuous run timers, and accumulative timers. Provided you plug in your refrigerator, the defrost timers that are constant or continuous will continue running. Accumulative defrost timers only operate when you turn on the compressor. Demand defrost timers are another name for cumulative defrost timers.
1. Three Terminal Devices
Almost all defrost timers have three terminals, one shared by the defrost heater circuit and the hermetically sealed compressor-motor circuit. One of the other two terminals is connected to the compressor motor, while the other has a connection to the heaters. The cold control supplies power to the defrost timer’s common terminal.
2. Cam Operated Contacts
Every timer, whether constant or accumulative run, has two sets of normally open, cam-actuated contacts. During the refrigeration phase of the cycle, the cam closes the first set of contacts, allowing electricity to flow to the compressor motor. The rotating cam allows the first set of contacts to open during the auto-defrost portion of the operation cycle, shutting down the compressor and closing the second set of contacts that sends electricity to the defrost heating elements.
3. Manual Operation
According to Parts Select, all defrost timers have a slot into which you can manually insert a screwdriver to operate the timer. You can manually open and close the internal contacts by turning the screwdriver in a clockwise direction. The compressor will shut down, and the defrost heaters activate when you hear the first click. The defrost heating elements will turn off or on. You can proceed by turning off the refrigerator. When you insert a screwdriver into the defrost timer and turn it clockwise, you can manually open or close the device’s internal contacts.
The first click as you move the screwdriver indicates that you turned off the compressor. It also indicates that the defrost heaters have been activated. The second click indicates that you have turned off the defrost heater and activated the compressor or fan mode.
Best Refrigerator With Defrost Timer
1. Midea WHD-113FSS1 Compact Refrigerator
The Midea WHD-113FSS1 Compact Refrigerator has the same features as a large refrigerator but in a smaller package. The streamlined free-standing design will complement any room and be used in protected outdoor spaces. It’s perfect for rooms away from the kitchen where you want to enjoy cold drinks and snacks.
A compact refrigerator from Midea cools quickly, quietly, and evenly, with no hot spots. It keeps ice solidly frozen and foods perfectly chilled. Because each space is unique, the doors are reversible. They can be attached on either the right or left side of the vehicle to allow access to the refrigerated compartments.
- The free-standing design works well in any setting.
- Designed using whisper-quiet technology.
- Adjustable legs and a reversible door that opens from the Left or right.
2. BLACK+DECKER BCRK43B 4.3 Cubic Foot Energy Star Mini Fridge
The BLACK+DECKER BCRK43B 4.3 Cubic Foot Energy Star Mini Fridge has a small footprint. It can be placed almost anywhere, including on the floor, a counter, or any other available space in a location where space is typically always at a premium. It has the same standard features as other refrigerators, including a full-width freezer, an ice cube tray, a full-width crisper drawer with a lid, a recessed door handle, manual defrost, and temperature control.
The interior includes clever storage choices in addition to the room. Each of the three shelves and door compartments is constructed of glass for a more refined feel. For individuals who use a tiny fridge for more than just keeping drinks, a dispenser is also there but doesn’t occupy the full door. In particular, this selection is also energy-efficient. It consumes about 226 kilowatt-hours of electricity annually, which is much less than that of competing models.
- Thoughtful door storage
- Reversible door
- Garage-ready design
- Non-adjustable shelves
Do all refrigerators have a defrost timer? This question has two answers: It is either yes or no. Some refrigerators on the market do not include a defrost timer, but most modern refrihgerators do.
Defrost timers are fantastic because they eliminate the time-consuming and labor-intensive inconvenience that manual defrosting entails. So, if you’re in the market for a new refrigerator, make sure it has auto-defrosting.
I’m a mom of three, a chef, a writer, and food blogger. I live in the suburbs of New Jersey where I love to cook and bake all day long. Cooking is a form of art and a way to preserve the beauty of nature. I create an edible canvas with fresh, seasonal ingredients.