How to check the thermal fuse in the refrigerator yourself: a step-by-step guide with photo

The thermal fuse is a small but critical part of the refrigerator that protects the compressor from overheating and short circuits. When it fails, the equipment either stops freezing or works intermittently. 90% of cases of sudden shutdown of the refrigerator are associated with a malfunction of the thermal protection or start-up relay, while the thermal fuse is often ignored.

If your refrigerator suddenly stops turning on, it makes clicks without starting motor or compressor runs for 5-10 seconds and turns off - the problem may lie in this particular part You can check it in 15 minutes, without resorting to the help of a technician. In this article, we will look at where the thermal fuse is located, how to test it with a multimeter, what signs indicate a breakdown, and what to do if the part is “burned out.”

For diagnostics, you don’t need professional skills - just the ability to use a screwdriver and a multimeter. If you don't have the device, we'll show you how to do without it. And for those who are afraid of making a mistake, we present resistance table for popular models of refrigerators Atlant, Indesit, Samsung and LG.

Where is the thermal fuse in the refrigerator and how to find it

Thermal fuse (sometimes called thermal protection or thermal fuse) is usually located in three places:

• 🔧 On the compressor - attached to the motor housing or built into the start-up relay. Most often found in models Biryusa, Atlant, Stinol.
• 🔌 Inside the electrical circuit —on the control board or next to the thermostat (typical for Samsung and LG with electronic control).
• ❄️ On the evaporator - in refrigerators with a system No Frost the fuse may be on the defrost heating element (for example, in Indesit or Ariston).

To get to the part, follow these steps:

1. Unplug the refrigerator from the mains and pull out the plug from the socket.
2. Remove the back cover (in most models it is attached to 4-6 screws).
3. Inspect the compressor - the thermal fuse looks like a small plastic or metal box with two terminals, often wrapped in heat-shrink tubing.
4. If there is nothing on the compressor, check the wires going from the motor to the relay - the fuse may be built into an open circuit.

If you cannot find the part visually, use the diagram of your model - it can be found in the instructions or on the sticker on the back of the refrigerator (usually next to the serial number). In the diagram, the thermal fuse is indicated as TH, TF or Thermal Fuse.

Signs of a thermal fuse malfunction: how to understand that it has burned out

The thermal fuse performs one task: it opens the circuit when it overheats. When it fails, the refrigerator behaves as follows:

• ⚡ The compressor does not start, but the relay clicks are heard (the motor is trying to turn on, but the circuit is open).
• ⏱️ The refrigerator works 5-30 seconds and turns off, then tries to start again after 2-3 minutes.
• 🔥 The compressor housing or the start-up relay heats up (intense heat is felt when touched).
• ❄️ In models No Frost does not work defrosting —ice builds up on the back wall of the freezer.
• 💡 The light inside the refrigerator is on, but the motor does not turn on (this indicates that the power is on, but the compressor circuit is open).

If the refrigerator does not respond at all when plugged in, the problem may be not only in the thermal fuse, but also in surge protector, thermostat or control board. To accurately determine the culprit, you need a comprehensive diagnosis.

How to check the thermal fuse with a multimeter: step by step instructions

The most reliable method of diagnosis is testing with a multimeter. For this you will need any tester (even the cheapest one for 300 rubles). Follow the algorithm:

1. Disconnect the refrigerator from the network and discharge the capacitor (if it is in the circuit) by shorting its terminals with a screwdriver with an insulated handle.
2. Remove the thermal fuse - carefully unsolder or disconnect the terminals. If the part is soldered into the board, you will have to unsolder it.
3. Switch the multimeter to continuity mode (diode or resistance icon).
4. Touch the fuse terminals with the probes:
   • 🔊 If you can hear sound signal (or the resistance is close to 0 Ohm) - the part is working.
   • 🚫 If on the screen 1 (break) - the fuse is blown and requires replacement.

For more accurate diagnostics, measure the resistance in mode 200 Ohm:

• 🟢 0.5–1.5 Ohm —the norm for most models.
• 🟡 More than 2 Ohm —the fuse is partially damaged (may trip when heated).
• 🔴 More than 10 Ohm or OL —break, replacement required.

Disconnected the refrigerator from the network|Discharged the capacitor (if any)|Removed the thermal fuse from the compressor|Switched the multimeter to continuity mode|Checked both outputs-->

Important! Some thermal fuses have temperature response threshold (for example, 120°C or 145°C). If the part is externally intact, but triggers when heated, it needs to be replaced - even if the multimeter shows 0 Ohm in a cold state.

Table of resistance of thermal fuses for popular refrigerators

Normal resistance values depend on the model and type of fuse. table for the most common refrigerators:

If your model is not in the table, follow the general rules:

• 🔹 Fuses on compressor usually have a resistance 0.5–1.5 Ohm.
• 🔹 Fuses defrost (in systems No Frost) — 0.2–0.8 Ohm.
• 🔹 If the resistance changes when heated (for example, it becomes OL after the hair dryer) - the part is faulty.

How to check a thermal fuse without a multimeter: 2 alternative methods

If you don’t have a tester at hand, you can use improvised methods. They are less accurate, but will help identify an obvious malfunction.

Method 1: Direct connection (testing method with a light bulb)

You will need:

• 💡 A light bulb on 220V (for example, from a desktop lamp).
• 🔌 Two wires with a plug.
• 🛠️ Insulating tape.

Sequence of actions:

1. Connect the light bulb in series with the thermal fuse (diagram: plug → fuse → light bulb → plug).
2. Insert the plug into the socket:
   • 💡 The light is on —the fuse is good.
   • 💡 The light bulb does not light —break in fuse.

How to replace the light bulb?

You can use any low-voltage indicator (for example, an LED with a 220 Ohm resistor), but it is easier to take an incandescent lamp - it can withstand power surges.

Method 2: Visual inspection + heating

Inspect the fuse for:

• 🔥 Blackening or melting housing.
• 💥 Blistering (especially if the part is in plastic shell).
• 🔌 Oxidation of terminals (green or white coating).

If there is no external damage, try heating the fuse with a hairdryer (at a distance of 10–15 cm) for 1–2 minutes. heating:

• 🔧 Refrigerator stops turning on — the fuse trips when the temperature rises (needs replacement).
• ✅ Refrigerator continues to work — detail is working (the problem is in another unit).

⚠️ Attention! Do not heat the fuse with an open flame (lighter, match) - this can permanently damage it. Use only a hair dryer at minimum power.

What to do, if the thermal fuse is burned out: repair or replacement

If diagnostics confirm a malfunction, you have two options:

Option 1: Replacement with a new one (recommended)

For replacement:

1. Buy a similar thermal fuse (marking indicated on the body of the old one). Popular models:
   • 🔹 KSD301 — for Atlant, Biryusa.
   • 🔹 15A250V —for Indesit, Ariston (defrost).
   • 🔹 KSD9700 — for LG, Samsung.

Install the part in place of the old one, observing polarity (if any).

Insulate the connections with heat-shrink tubing or electrical tape.

The cost of a thermal fuse is from 50 to 300 rubles (depending on the model). Never replace it with a “bug” (a jumper made of wire) - this will lead to overheating of the compressor and a fire!

Option 2: Temporary restoration (only for experienced ones)

If you urgently need to start the refrigerator, but there is no new fuse, you can:

1. Carefully open the case fuse (cut with a knife).
2. Check the integrity of the spring contact inside - sometimes it simply moves away from the terminal.
3. If the contact is intact, temporarily connect the terminals with a soldering iron (but do not leave it like that for long!).

⚠️ Attention! A “bug” made of wire or foil - This is direct path to fire. The thermal fuse opens the circuit for a reason, but to prevent overheating. Without it, the compressor can burn out, and the insulation of the wires can ignite.

After replacement, check the operation. refrigerator:

• ✅ The compressor should start without clicks and run smoothly.
• ✅ The motor housing should not heat up above 50–60°C.
• ✅ In models No Frost after 8–12 hours, ice on the evaporator should melt.

Common mistakes when checking and replacing a thermal fuse

Even experienced craftsmen sometimes make mistakes that lead to repeated breakdowns or failure of other components. This is what cannot be done:

• 🔌 Check the fuse under voltage it is life-threatening and dangerous. may damage the multimeter.
• 🔥 Use a fuse with a different temperature threshold (for example, install 105°C instead of 120°CThis will lead to false alarms or, conversely, lack of protection.
• 🛠️ Forget about the capacitor —if you do not discharge it before work, you can get an electric shock.
• 🔧 Install a fuse without thermal paste (if it is attached to the compressor This worsens the heat dissipation and leads to false ones). operation.
• ❄️ Ignore the cause of operation. If the fuse is blown, it means there was a cause of overheating (clogged capacitor, faulty relay, freon leak) Without eliminating the root of the problem, the new fuse will quickly fail.

If after replacing the fuse the refrigerator does not turn on again, check:

• 🔧 Start-up protection relay - it may be the cause of overheating.
• 🔌 Thermoregulator - if it is faulty, the compressor works without stopping and overheats.
• ⚡ Compressor windings - ring them for a short circuit.

FAQ: Frequently asked questions about thermal fuses in the refrigerator

Is it possible to repair a thermal fuse, or just replace it?

A thermal fuse is disposable partAfter tripping, its internal contact is destroyed, and it is impossible to restore it. connection (soldering, bug) is only permissible for emergency start-up of the refrigerator for 1-2 days, but not for continuous operation.

Which thermal fuse should I buy as a replacement if the marking is erased?

Focus on:

• 🔹 Refrigerator model (find the diagram in the instructions).
• 🔹 Temperature threshold:
  • For the compressor - 120–145°C.
  • For defrosting No Frost — 100–110°C.
• 🔹 Resistance (should be 0.5–1.5 Ohm).

Universal options: KSD301 (for compressor) or 15A250V (for defrosting).

Why does the new thermal fuse burn out again?

This indicates a system problem:

• 🔥 Overheating of the compressor due to:
  • clogged capacitor (dust, dirt);
  • faulty fan (in models No Frost);
  • freon leakage (the motor runs without stopping).
• ⚡ Short circuit in the compressor windings or start relay.
• 🔌 Unstable voltage on the network (a stabilizer is needed).

Before replacing the fuse be sure to check these components!

Can a refrigerator operate without a thermal fuse?

Technically yes, but this is extremely dangerous:

• ⚡ Risk fire due to overheating of wire insulation.
• 💥 Risk compressor failure (replacement cost - from 5,000 rubles).
• ⚠️ Loss of warranty (if the refrigerator is under warranty, repairs will not be paid).

If the fuse has burned out, but there is no new one - unplug the refrigerator and do not use it until the part is replaced.

Where to buy a thermal fuse for a refrigerator?

Purchase options:

• 🛒 Spare parts stores for household equipment (for example, "Rembyttekhnika", "220 Volt").
• 🌍 Online stores:
  • AliExpress (cheap, but long);
  • Yandex Market, Ozon (fast, but more expensive).
• 🔧 Service centers (can be ordered with installation).

Average cost - from 50 up to 500 rubles depending on type.