Sudden defrosting of food or, conversely, turning it into an ice block are sure signs that thermostat your refrigerator is out of order. In brand units Nord this part is a key element of the temperature control system, and its failure makes further food storage impossible. Fortunately, the design of these refrigerators allows you to replace thermostat on your own, if you have minimal skills in working with tools and follow safety precautions.
Before you start disassembling, you need to make sure of the diagnosis, so how symptoms of a malfunctioning thermostat are often confused with a breakdown of the start relay or a freon leak. If the compressor hums but does not start, or runs nonstop without turning off for hours, the problem most likely lies in the temperature sensor. In this article we will analyze in detail the process of diagnostics, selection of analogues and replacement of the thermostat in refrigerators Nord.
Particular attention should be paid to safety, since the work will be carried out in close proximity to electrical contacts. Although there is no voltage of 220 volts when the plug is pulled out, there may be residual charges in the capacitors inside the system, and careless handling of the wiring can lead to a short circuit when first turned on. Therefore Before starting any work, be sure to disconnect the refrigerator from the power supply wait until the chambers are completely defrosted if there is ice.
Diagnostics of a thermostat malfunction
The first step in any repair is to accurately identify the problem. In refrigerators Nord the thermostat is responsible for opening and closing the electrical circuit of the compressor depending on the temperature in the chamber. If this mechanism is stuck in the open position, the motor-compressor will not receive a signal to start, and the refrigerator will become warm. If the contacts stick in the “closed” position, the unit will operate continuously, freezing the contents.
For an initial check, you can use the exclusion method. Try turning the control knob to its extreme position (usually counterclockwise all the way or to minimum). If the characteristic click is not heard and the compressor is silent, this is an alarming sign. However, a more reliable way is to directly close the thermostat contacts, which simulates its operation at a very low temperature.
- 🔍 Disconnect the refrigerator from the network and remove the plastic cover of the thermostat to gain access to the contact group.
- 🔌 Carefully remove the terminals from the thermostat contacts and connect them together directly (using a jumper or twist).
- ⚡ Turn on the unit: if the compressor works, then the problem is definitely in the thermostat, and it needs to be changed.
It is worth noting that in some models Nord with the No Frost system or drip defrosting, in addition to the main thermostat, there may be additional sensors defrost. Their malfunction can give similar symptoms, so it is important to check the main compressor control circuit. If, after closing the contacts, the motor hums but does not start, the problem may be in the start relay, and not in the temperature sensor.
⚠️ Attention: When closing the contacts, make sure that the wires do not touch the metal parts of the refrigerator body to avoid sparking and damage to the wiring.
Diagnostics completed, and if you are convinced that the thermostat is the culprit, we move on to preparation. You should not ignore this stage, since an incorrect assessment of the condition of adjacent components can lead to repeated repairs in a short time.
Selecting a suitable spare part for replacement
Selecting the right one thermostat is a critical stage on which the durability of the repair depends. Refrigerators often used thermostats from various manufacturers, such as Ortoba. The main differences are the length of the capillary tube, the on/off temperature and the mounting method. Nord thermostats from various manufacturers were often used, such as Tam, K-59, Ranco or Ortoba. The main difference is the length of the capillary tube, the on/off temperature and the method of attachment.
The capillary tube is a thin copper conductor that is filled with a temperature-sensitive gas or liquid. It is she who transmits data about the temperature inside the chamber to the mechanical part of the thermostat. The length of this tube should correspond to the original or be a little longer (the excess can be carefully rolled up), but in no case less, otherwise the sensor will not reach the desired control zone.
When purchasing, pay attention to the markings. The numbers and letters in the model code indicate the temperature range of operation. For example, thermostats marked K-59 are often suitable for single-chamber refrigerators, while two-chamber refrigerators may require series models K-50 or their modern analogues.
| Parameter | Description | Importance |
|---|---|---|
| Capillary length | Distance from the body to the sensor (usually 0.7m - 2.5m) | High: the short one will not reach, the long one can be twisted |
| Mounting type | Threaded or snap-on | Medium: fasteners can be adapted |
| Temperature conditions | Compressor on/off range | Critical: affects storage quality |
Do not try to save money by purchasing universal Chinese analogues without markings, as their calibration is often inaccurate. It is better to find an original analogue or a high-quality substitute from a well-known brand that is guaranteed to fit your model Nord. In specialized spare parts stores, sellers often have compatibility tables, which greatly simplifies the search.
Where can I find the markings of an old thermostat?
The markings are usually applied to the metal body of the thermostat or to the plastic knob of the regulator. If the inscription is erased, the model can be found in the technical documentation of the refrigerator or on the nameplate inside the chamber, which indicates the type of refrigerant and thermostat used.
Necessary tools and preparation of the workplace
To successfully replace the thermostat in the refrigerator Nord you do not need complex professional equipment, but a set of tools should be at hand. The bulk of the time will be taken by dismantling the plastic panels and careful work with the wiring, so accuracy and care are important.
First of all, you will need a standard set of screwdrivers: Phillips and flathead screwdrivers of different sizes. In some models Nord the screws may be hidden under decorative plugs, so it would be useful to have a thin awl or knife to remove them carefully. Also prepare pliers with thin jaws for working with terminals.
- 🛠️ Set of screwdrivers (phillips PH1, PH2 and flat).
- 🔧 Pliers or pliers for fixing terminals.
- ✂️ Wire cutters or side cutters for trimming the excess length of the capillary (if necessary).
- 🧤 Insulating tape or heat shrink to protect the connections.
The work place should be well lit, as the inside of the refrigerator, especially in the area of the lampshade and thermostat, are often in the shade. Cover the floor in front of the refrigerator with a soft cloth or cardboard so as not to damage the coating and not to lose small screws that tend to roll into the most inaccessible places.
⚠️ Attention: The capillary tube of the thermostat is very thin and fragile. Do not bend it at an acute angle and do not allow impacts, as damage to the tightness of the tube will lead to incorrect operation of the new thermostat.
Free up space around the refrigerator in advance in order to have access to it from all sides. Although thermostat replacement is usually done from the front, access to the rear wall may be necessary to check the condition of the compressor after repair. Make sure that the room is dry and there are no drafts that could interfere with work.
Removing the old thermostat
The process of removing the old thermostat in refrigerators Nord begins with dismantling the plastic cover that hides the regulator mechanism. In most models, to do this, it is enough to carefully pry off the cover with a flat screwdriver or remove the decorative handle, which is held on by latches.
After removing the cover, you will see the thermostat itself, built into the wall of the refrigerator compartment. It can be fastened with screws or simply inserted into a mounting hole with a seal. Your task is to carefully remove the thermostat housing without damaging the capillary tube, which goes deep into the chamber or behind the casing.
The next step is to disconnect the electrical wires. Before doing this, it is strongly recommended to take a photo of the connection diagram or sketch it, since the color marking of the wires may differ from one manufacturer to another. Typically, two or three wires go to the thermostat: phase, neutral, and sometimes a ground wire or indicator lamp.
Carefully remove the terminals from the thermostat contacts. If they are oxidized or stuck, do not pull them sharply so as not to break the wire. It is better to slightly warm the terminal with a hairdryer or treat it with penetrating lubricant. After disconnecting the wires, you can completely remove the thermostat by pulling the capillary tube out of the technological hole.
☑️ Preparation for dismantling
If the capillary tube is frozen to the evaporator or wall, do not try to pull it out by force. Wait until completely thawed, or carefully use warm water (not boiling water!) to defrost the ice around the tube. Rough mechanical impact can damage the evaporator, which will lead to freon leakage and expensive repairs.
Installation of a new thermostat and connection
Installation of a new one thermostat is carried out in the reverse order of dismantling. First, you need to pull the capillary tube of the new sensor into the process hole. Act slowly and smoothly, making sure that the tube fits in smoothly and does not jam against the edges of the hole.
The length of the capillary tube of the new thermostat may differ from the original. If it is longer, the excess should be carefully rolled into rings with a diameter of at least 3-4 cm and placed behind the back wall of the refrigerator or in free space, avoiding kinks. If the tube is too short, it may not be long enough to install the sensor correctly, and the part will have to be replaced.
Fix the thermostat housing in the seat. Make sure that the rubber seal is tight so that cold air from the chamber does not escape through the hole, and warm air does not get in, causing condensation. Install the decorative trim and the regulator knob.
The most crucial moment is connecting the wires. Use a photo or diagram you took earlier. Typically, wires are connected to contacts without observing polarity, but it is important to securely fix the terminals. If the old terminals are damaged, it is better to replace them with new ones by crimping them with a special tool or carefully soldering them (observing safety precautions).
After connecting all the wires, check the reliability of the connections again. Wires should not touch moving parts (if any) or hot elements. Reassemble all the plastic panels in the reverse order.
Checking operation and setting the temperature
After assembly is complete, the refrigerator can be plugged in. Don't expect immediate results: the compressor will take time to build up speed and start cooling. In the first minutes of operation, listen to the sound of the motor: it should run smoothly, without strong vibration or extraneous knocks.
The first temperature setting is an important step. Set the thermostat knob to the middle position. After 20-30 minutes of operation, check the temperature in the chamber. If the refrigerator begins to freeze too much or, on the contrary, does not gain cold, you may need to adjust the position of the capillary tube or the adjusting screw inside the thermostat (if it is available and you have experience).
- 🌡️ Let the refrigerator operate for 2-3 hours without loading food to stabilize the temperature.
- 🔊 Watch the cycle operation: the compressor should be turned off and on periodically.
- ❄️ Check for excessive frosting on the rear wall or evaporator.
If the compressor has been running non-stop for more than an hour and the temperature in the chamber drops below normal, the new thermostat may have a different temperature response range. In this case, it may be necessary to replace the part with a model with different characteristics or adjust the internal mechanism.
⚠️ Attention: Do not load the refrigerator with food immediately after turning it on. An empty chamber cools down faster, and you can more accurately assess the effectiveness of the new thermostat.
Frequently asked questions (FAQ)
Is it possible to replace the thermostat in a Nord refrigerator with an analogue from another manufacturer?
Yes, you can. The main thing is that the overall dimensions, the length of the capillary tube and the temperature range of operation match. Analogs from Tam, Ranco or Kaleviare often used, which have similar characteristics.
Why does the new thermostat click, but the compressor does not start?
This may indicate a malfunction of the compressor start relay or the motor itself. The thermostat only completes the circuit, but if the relay does not operate or the engine is burned out, starting will not occur. Also check for voltage at the thermostat input.
Do you need to recharge the freon after replacing the thermostat?
No, replacing the thermostat does not affect the refrigeration circuit if you did not damage the evaporator capillary tube during dismantling. The system remains sealed and refilling the refrigerant is not required.
How can you tell if the thermostat capillary tube is installed incorrectly?
If the tube does not fit tightly to the evaporator or is in the wrong temperature zone, the refrigerator will work intermittently: it will either turn on frequently or not turn off for a long time. It is important to ensure good thermal contact of the sensor.
How long does it take to replace a thermostat with your own hands?
For an experienced technician, the process takes 30-40 minutes. For a beginner, taking into account preparation, searching for tools and carefully disassembling the plastic, this can take from 1 to 2 hours.