Selecting a relay for a refrigerator compressor: instructions with tables and tips

The refrigerator compressor relay is a small but critical part. Its serviceability determines whether the motor will start, whether there will be overheating and whether the overload protection will work. If the refrigerator suddenly stops freezing, hums but does not start, or the compressor runs without stopping, the relay may be the culprit. However choosing a new relay is not as easy as it seems: you need to take into account the type of compressor, current characteristics, mounting design and even the brand of the refrigerator.

In this article we will look at how correctly identify a faulty relay is found, what parameters are important when choosing a replacement, and why universal a relay is not always a good idea. You will also find a compatibility table for popular compressor models Danfoss, Embraco and Secop, and at the end - answers to frequently asked questions about diagnostics and installation.

Symptoms of a faulty compressor relay

Before you run to the store for a new relay, make sure that this is the problem. Typical symptoms:

• 🔊 Refrigerator buzzes, but does not start - protection is triggered due to incorrect starting current.
• ⚡ The compressor turns on for 1-2 seconds and immediately turns off (symptom "clicks").
• ❄️ The motor runs continuously without turning off to rest, which leads to overheating.
• 🔥 A burning smell or melted plastic appears on the relay body.

It is important to distinguish a relay failure from a malfunction of the compressor itself or thermostat. For example, if the refrigerator does not respond at all when plugged in, the problem may be surge filter or control unit. And if the compressor starts, but does not freeze, it is to blame freon leak or a clogged capillary tube.

Types relays: what is the difference and which one to choose

Relays for refrigerators are divided into three main types, and a universal relay is not always suitable. Let's figure out what the difference is:

1. Start protection relays (the most common) - they combine the functions of starting the compressor and protecting against overheating. Used in 90% of household refrigerators.
2. Start relays —only start the motor, protection is implemented separately (found in older models or industrial installations).
3. Electronic relays —modern devices with soft start that reduce the load to the network. Installed in refrigerators No Frost and inverter models.

Suitable for most household refrigerators (Atlant, Indesit, Samsung, LG). start-protective relay. But there are nuances:

• 🔧 Mechanical relays (with a spring and core) is cheaper, but less accurate. Suitable for compressors with a power of up to 140 W.
• 📊 Electronic (with a control board) are more expensive, but more reliable and quieter. Mandatory for inverter compressors.
• 🔄 Relays with a posistor (thermistor) - self-regulating, adjusted to the compressor current. Used in models Liebert and Beko.

Key parameters for selecting a relay

For a new relay to work correctly, it must meet four basic parameters:

1. Compressor current (indicated in amperes, for example, 1.2–1.4 A). This is the most important parameter - if the relay current is lower than that of the compressor, the motor will not start.
2. Mounting type: the relay can be fixed on the compressor latches, screws or terminal block.
3. Network voltage: most relays are designed for 220–240 V, but for three-phase compressors (industrial refrigerators) you need a relay for 380 V.
4. Winding resistance (for electronic relays). Must match the parameters of the compressor (indicated in ohms, for example, 20 Ω ± 5%).

Where can I get this data?

• 📄 On compressor nameplate (metal plate on the motor housing). Look lines Rated Current (rated current) and Voltage.
• 🔍 In refrigerator passport or on the manufacturer’s website (section “Technical Specifications”).
• 🛠️ On housing of the old relay (type marking DANFOSS 103N0210 or EMBRACO EGX 1.5).

How to read the compressor nameplate?

On the plate compressor are usually indicated:

- Model — motor model (for example, Danfoss NL12FX).

- Input — power consumption in watts (for example, 120 W).

- RLA (Rated Load Amps) - rated current in amperes (the main parameter for a relay!).

- LRA (Locked Rotor Amps) - starting current (needed to select a starting capacitor, if any).

If the nameplate is erased, you can find the compressor model by the serial number of the refrigerator on the manufacturer's website.

Compatibility table of relays and compressors

Below is a compatibility table for popular models compressors and relays. If your model is not in the list, focus on current (RLA) current (RLA) mount type.

⚠️ Attention: If your refrigerator is equipped with inverter compressor (for example, Samsung Digital Inverter or LG Smart Inverter), a mechanical relay will not work! analogue from the manufacturer. original electronic relay with the same marking or an analogue from the manufacturer.

How to choose a relay by refrigerator brand

If you are not sure about the compressor model, you can focus on make and model of refrigerator. Below is a short guide to popular brands:

• 🏠 Atlant, Biryusa, Pozis: most often there are compressors Danfoss or Secop with relays RTK-1, 103N0012.
• 🌍 Indesit, Ariston, Hotpoint: compressors Embraco (series EG, NE) with relays ER2300–ER3500.
• 📱 Samsung, LG (since 2015 g.): electronic relays DA97-08323A (Samsung), 6871W1Z002A (LG).
• ❄️ Beko, Vestfrost: relay with a posistor PTC-14 or Danfoss 103N0210.

For precise selection:

1. Find refrigerator serial number (usually on the sticker inside the camera or on the back).
2. Enter it into a search on the manufacturer's website or in spare parts catalogs (for example, PartMaster, Searspartsdirect).
3. In the results, look for the section Compressor Relay or Start Relay.

Find the serial number (SN) of the refrigerator

Check the compressor model for nameplate

Check the current (RLA) of the compressor and relay

Make sure the mount is compatible

Buy the original or a certified analogue-->

Errors when choosing and installing a relay

Even experienced craftsmen sometimes make mistakes when replacing a relay. Here the most common mistakes and how to avoid them:

• ⚡ Current mismatch: if the relay is designed for 1.2 A, and the compressor consumes 1.5 A, the motor will overheat. Always take a relay with current margin of 10–15%.
• 🔌 Incorrect connection of the terminals: if mixed up Common (C), Start (S) i Run (R), the compressor will burn out. The connection diagram is usually marked on the relay body.
• 🛠️ Use of a universal relay without checking: some “universal” models (for example 3-in-1) are not suitable for compressors with high starting current.
• 🔧 Ignoring the posistor: in a relay with a thermistor (PTC), you cannot replace only the mechanical part - you need to change the entire unit.

⚠️ Attention: If after replacing the relay the compressor still does not start, do not try to turn it on repeatedly. this may lead to an inter-turn short circuit of the windings. Maximum of 2-3 attempts with an interval of 5 minutes!

Before installing a new relay:

1. Check resistance of the compressor windings with a multimeter (norm: 20–40 Ω for the working winding, 10–20 Ω for the starting winding).
2. Make sure that relay contacts are clean (oxidation or carbon deposits increase the resistance).
3. Secure the relay tightly to the compressor housing — vibration can break contact.

Where to buy a relay and how not to run into a fake

Relays for refrigerators are sold in:

• 🛒 Specialized spare parts stores (for example, Holod-Service, FrostMaster).
• 🌐 Online platforms: AliExpress (for rare models), eBay, Amazon, as well as Russian sites like Beru or Ozon.
• 🔧 Service centers for repairing refrigerators (sometimes they sell used original parts).

How to distinguish an original from a fake:

• 🏷️ On the body of the original relay there should be clear markings with the model, current and manufacturer's logo.
• 🔍 Check weight and material: fakes are often lighter and made of fragile plastic.
• 📦 Included with a branded relay is instructions or connection diagrams.

⚠️ Attention: Cheap relays without markings (for example, “universal” ones for 200–300 rubles) can not only quickly break down, but burn the compressor due to unstable starting current. Savings of 500-1000 rubles will result in repairs of 10-15 thousand.

FAQ: Frequently asked questions about selecting a relay

Is it possible to replace a relay with latches with a relay with a screw fastening?

Technically yes, but it will be required modify the fastening (for example, drill holes for screws or use an adapter plate). The main thing is that current characteristics and connection diagram in some cases it is easier to find a relay with the original type of fastening.

How to test a relay with a multimeter?

Switch the multimeter to resistance testing mode (200 ΩConnect the probes to the terminals S i C:

• At room temperature there should be resistance infinite (open).
• If you cool the relay (for example, put it in the freezer for 10 minutes), the resistance should fall to 0 (closed).

If the resistance does not change, the relay is faulty.

What to do if there is no nameplate on the compressor?

Determine the compressor model by:

1. Serial number of the refrigerator (look in the manufacturer's database).
2. The shape and color of the compressor (for example, Danfoss usually black, Embraco grey).
3. Photos - upload it to services like Google Lens or ask on the forums (for example, MasterCity or Cold-Forum).

As a last resort, take a relay with regulated current (for example, Danfoss 103N0050).

Why does a new relay burn out through week?

Probable causes:

• 🔥 Interturn short circuit in the compressor —check the resistance of the windings.
• ⚡ Voltage surges in network —install a stabilizer.
• 🔌 Poor contact in the terminals - strip and crimp the wires.
• 🌡️ Compressor overheating due to a dirty capacitor or faulty fan.

If the relay burns out again - diagnose the compressor and electrics of the refrigerator.

Is it possible to install a relay from another refrigerator?

It is possible if:

• The current matches (RLA) and type of fastening.
• The connection diagram (C-S-R) is identical.
• The relay is designed for the same compressor power.

For example, a relay from Indesit with a compressor Embraco EGX 1.2 is suitable for Ariston with the same motor. But a relay from Samsung with an inverter compressor will not change to a regular one. data-i="308">How many copper tubes are in the refrigerator: calculation, types and replacements Atlant.