Brand refrigerators Nord are deservedly famous for their reliability and durability, however, even the highest quality equipment requires maintenance over time. One of the most common malfunctions that owners of these units encounter is the failure of the thermostat. It is this component that is responsible for maintaining a given temperature regime inside the chambers, and its breakdown leads to either complete defrosting of products or their deep freezing.
Before calling a technician or rushing to a service center, you should consider the possibility of self-repair. Replacing the thermostat - this is a procedure accessible to a person with basic skills in handling tools and an understanding of the basics electrical engineering. In this article, we will analyze in detail the process of diagnosing and replacing the temperature sensor, paying special attention to the nuances of working with models Nord.
A timely response to malfunctions of the thermostat allows you to avoid more serious problems with the compressor, which can burn out from constant operation without stopping. It is important to understand that thermostat (or thermostat) is a mechanical or electronic device that closes and opens an electrical circuit depending on the temperature of the evaporator. If you notice that the refrigerator Nord stops turning off or, conversely, does not start at all, the problem most likely lies here.
Diagnostics of thermostat malfunction
The first step in any repair is to accurately determine the cause breakdowns. The absence of cold or, conversely, the formation of a “fur coat” does not always indicate a malfunction of the sensor. Sometimes the reason may lie in a freon leak or a breakdown of the start relay, so it is important to carry out initial visual and acoustic diagnostics. If the compressor runs continuously, without turning off even with the minimum settings of the regulator, this is a clear sign that the contacts inside the thermostat are “stuck” in a closed state.
The opposite situation, when the refrigerator is silent and does not make any sounds, may also indicate an open circuit inside the thermostat. In this case, the electrical signal simply does not reach the engine, and the cooling system does not start. For a more accurate check, you can use the exclusion method: try to forcibly close the contacts on the thermostat itself (after disconnecting the refrigerator from the network!). If, after closing the contacts and connecting to the network, the compressor starts working, then thermal sensor requires replacement.
⚠️ Attention: Carry out all manipulations with electrical contacts and wiring only with the refrigerator completely disconnected from the power supply. Failure to follow safety rules may result in electric shock or short circuit.
There is another indirect sign of a malfunction - the absence of a characteristic click when turning the temperature control knob. In good condition, when scrolling the knob from minimum to maximum, a clear mechanical click should be heard, indicating the opening or closing of the internal contacts. If the knob rotates freely, without resistance or sound, the internal mechanics of Nord T-133 or a similar thermostat are most likely broken.
Tools and preparation for work
To successfully carry out work on replacing the thermostat, you do not need complex professional tools. A standard DIY kit will be sufficient to dismantle old parts and install new ones. The main thing is to ensure good lighting of the working area and free access to the top of the refrigeration chamber, where the control unit is usually located.
You will need the following tools and materials:
- 🔧 Screwdrivers (Phillips and flat) - for removing panels and terminal clamps.
- 🔪 A sharp knife or scalpel - for carefully removing insulation or stripping contacts if necessary.
- 🧤 Dielectric gloves - to protect hands and prevent static discharge.
- 📸 Smartphone - for photographing the wiring diagram before disconnecting them.
Particular attention should be paid to the selection of a new spare part. Thermostats for refrigerators Nord can have various parameters, such as the length of the capillary tube, the on/off temperature and the type of contacts. The most common models installed on equipment of this brand are TAM 133, TAM 145 or their analogues from other manufacturers (for example, Ortiz, K-59). It is important that the length capillary tube of the new thermostat matches the original or is slightly longer (the excess can be carefully rolled into a ring).
☑️ Preparation for repair
Before starting disassembly, be sure to defrost the refrigerator if there is ice in the chambers. Working with wet components and condensation can be hazardous, and water coming into contact with electrical contacts will cause corrosion or short circuits. It is also recommended to empty the top shelf of the refrigerator compartment so that nothing interferes with access to the lampshade and thermostat.
Access to the thermostat: disassembling the unit
In most refrigerator models Nord the thermostat is located inside the refrigerator compartment, most often in the upper right corner. Access to it is blocked by a plastic casing or lampshade. The process of removing this protection may vary depending on the specific modification of the unit, but the general algorithm of actions remains similar.
First you need to remove the temperature control knob. It can simply be removed by hand, but sometimes you need to carefully pry it off with a flat-head screwdriver if the design involves a hidden stopper. After removing the handle, you will see a plastic panel that is secured with latches or screws. Be careful: the plastic in old refrigerators becomes brittle and can crack if handled carelessly.
⚠️ Attention: Do not use force when removing plastic panels. If the element does not budge, check for hidden screws under decorative plugs or stickers.
Next, the algorithm of actions is as follows:
- 📷 Take a photo of the current location of the wires and terminals - this is your insurance during assembly.
- 🔌 Disconnect the connectors or terminals from the thermostat contacts, having previously noted their color markings.
- 🔩 Unscrew the screws securing the thermostat housing to the chamber wall or bracket.
- ❄️ Carefully remove the capillary tube from the evaporator (it may be secured in a special hole or pressed with a bar).
It is important not to damage the capillary tube when removing. It is a thin copper tube filled with refrigerant that reacts to changes in temperature. If a crack appears in it or it is pinched, the thermostat will no longer correctly read the temperature, and the repair will have to start again. In some models Nord the tube passes through the door seal or is hidden behind a decorative strip, which requires additional attention when dismantling.
What to do if the capillary tube is too long?
If the length of the new thermostat tube exceeds the required length, do not cut it or bend at an acute angle. Carefully roll the excess into a tight ring with a diameter of at least 5 cm and place it inside the refrigerator body, securing it so that it does not touch moving parts or hot elements.
Connection diagram and pin markings
Correctly connecting the wires is a critical step in replacing the thermostat. An error in the wiring can result in the refrigerator not starting, running non-stop, or worst of all, causing a short circuit. The contact markings are usually marked on the body of the thermostat, but over time it can be erased, so it is important to know the standard color coding.
Let's consider a typical connection diagram for the most common thermostat TAM 133which is often installed in refrigerators Nord. Typically the device has three or four contacts. The main ones are responsible for supplying power to the compressor and the defrosting circuit (if there is one). The colors of the wires may vary depending on the year of manufacture of the refrigerator, but the following combinations are most often found.
Below is a table of contacts and functions for the standard circuit:
| Designation on the terminal | Wire color (typical) | Function | Where to connect |
|---|---|---|---|
| 3 (or L) | Red / Orange | Voltage input (Phase) | From mains / Relay |
| 4 (or 1) | Black / Brown | Output to compressor | To compressor |
| 6 (or 2) | White / Yellow | Defrost circuit / Lamp | To heating element or lamp |
| Grounding | Green / Yellow-green | Protective grounding | To the body |
When replacing the thermostat with an analogue from another manufacturer (for example, Ortiz instead of TAM), the numbering of the contacts may differ. In such cases, you need to rely on the electrical diagram supplied with the new sensor, or use a multimeter to “test” the contacts. In normal condition (at room temperature), the contacts responsible for starting the compressor should be closed.
If you are not sure about the correct connection, it is better to double-check the information in the technical documentation for your specific model Nord. An incorrect connection can damage not only the new thermostat, but also more expensive components, such as a compressor or control unit.
Installing a new thermostat
The process of installing a new thermostat is carried out in the reverse order of dismantling. First, the capillary tube must be positioned correctly. Its sensitive end must be tightly fixed in a special socket on the evaporator or pressed against its surface with a metal strip. Poor contact of the tube with the evaporator will lead to incorrect temperature reading and frequent switching on/off of the compressor.
Make sure that the tube is not kinked or kinked. After fixing the tube, install the thermostat housing in its original place and secure it with screws. Next, connect the wires according to the photographs or diagram taken earlier. It is recommended to re-stripe the ends of the wires if there are oxides or traces of old insulation on them to ensure reliable electrical contact.
After connecting all the wires, check that the connectors are securely fixed. They should fit tightly, without play. If screw terminals are used, make sure they are tight but not overtightened to avoid damaging the threads or wire. Then reinstall the plastic casing and temperature control knob.
⚠️ Attention: Make sure that the capillary tube does not touch moving parts, sharp metal edges or hot elements (in the case of the compressor area) to avoid damage during operation.
Final The mechanical assembly step is to check that the control knob rotates freely and does not touch the housing elements. If the handle rests against the plastic, the thermostat may not be installed completely or the wrong handle model has been selected.
Checking functionality and setting
After assembling all components, you can begin testing. Plug in the refrigerator and set the thermostat knob to the middle position (usually number 3 or 4 on the scale). After a few seconds, you should hear a characteristic click and the compressor starts. If the refrigerator is silent, try turning the knob towards maximum cold - you should hear a power click.
Let the refrigerator operate for 30-40 minutes. During this time, the temperature inside the chamber should begin to decrease. Check if the compressor turns off when the set temperature is reached. If the refrigerator runs without stopping for more than an hour and the food in the chamber is clearly freezing, the thermostat may need adjustment.
On the body of some thermostats (for example, TAM 133) there are adjustment screws hidden under a seal or plastic plug:
- 🔧 Range screw - changes the entire on/off temperature (shifts the operating range).
- 🔧 Differential screw - changes the temperature difference between turning on and off.
It is not recommended to make adjustments without special instruments and skills, as the factory settings can be reset. If the new thermostat is not working correctly (turning on too often or not turning off), it is better to replace it with another one with the appropriate parameters rather than trying to adjust it.
Why does the refrigerator click but does not start?
If you hear the thermostat click, it is followed by a click from the start relay, but the compressor hums and does not start (or just clicks), The problem is most likely not in the thermostat, but in the start relay or the compressor itself. In this case, the thermostat properly sends a signal to start.
Frequently asked questions (FAQ)
Is it possible to use a thermostat from another manufacturer, for example, Ortiz or K-59, instead of TAM?
Yes, it is possible if the main parameters match: the length of the capillary tube, the type of fastening and the temperature range. Often Ortiz 667 is a direct analogue of TAM 133. The main thing is to connect the contacts correctly, since their numbering may differ.
What to do if the capillary tube of the new thermostat is longer than the old one?
The excess tube cannot be cut off. It must be carefully rolled into a ring with a diameter of at least 5-6 cm and placed inside the refrigerator body (usually behind the back wall or in a niche), fixing it so that the tube does not vibrate or touch sharp edges.
How can you tell that the thermostat is “lying” and shows the wrong temperature?
If the food in the refrigerator is clearly freezing or, conversely, deteriorate, although the regulator knob is in the usual position, and at the same time the compressor operates in an abnormal mode (too long or in too short cycles), this is a sign of a sensor malfunction. An accurate check can only be carried out using a thermometer, placing it in the chamber.
Is it necessary to completely defrost the refrigerator before replacing the thermostat?
Yes, this is a mandatory safety requirement and technological necessity. Moisture can cause a short circuit when connecting the wires, and ice will make it difficult to access the components and can damage the capillary tube during dismantling.
Why does the new thermostat click, but the refrigerator does not turn on?
The click means that the thermostat mechanics are working and the contacts are closing. If the refrigerator does not respond, the problem may be a lack of voltage at the thermostat input, faulty wires, the start relay, or the compressor itself. You need to test the circuit with a multimeter.