Localization of copper alloys in the design of old refrigerators

The question of where exactly copper is located in old refrigerators often arises among those who recycle household appliances or want to hand over non-ferrous metals to collection points. Old Soviet and early foreign models of units, produced before the mid-90s, contained significantly more non-ferrous metals than modern energy-efficient devices. Understanding the design of the heat exchange circuit and the electrical part allows you to get the most out of the valuable resource without damaging it or mixing it with ferrous metal or aluminum.

Copper in refrigeration equipment is valued for its exceptional electrical and thermal conductivity, as well as its resistance to corrosion. It was these properties that made it an indispensable material for creating a closed refrigerant circulation cycle. However, in pursuit of cheaper production, modern engineers are increasingly replacing pure copper with aluminum or copper-plated steel, which reduces the weight of the product, but makes it less suitable for recycling as non-ferrous scrap.

Before proceeding with disassembly, it is necessary to clearly understand the difference between designs of different eras. Soviet refrigerators, such as "ZIL", “Saratov”, “Biryusa” or “Morozko” are designed with a margin of safety and using traditional materials. In them, copper elements make up a significant part of the payload weight. At the same time, later models can hide their wealth under layers of insulation or replace them with bimetallic pipes.

The main heat exchange circuit: condenser and evaporator

The most obvious and voluminous part where copper is located in old refrigerators is the system tubes surrounding the body or located inside the chambers. In the classic refrigeration cycle, the refrigerant passes through a condenser, where it gives off heat, and an evaporator, where it takes in cold. In older units, especially those produced in the 70s and 80s, these elements were almost always made of pure copper or brass.

The capacitor in older models was often a coil mounted externally on the rear wall of the case. It could be painted black, which sometimes misled inexperienced disassemblers into mistaking it for steel. However, if you clean a small section of the pipe with a knife or file, the characteristic reddish-yellow sheen of copper will be revealed under the paint. In some models, for example ZIL-63 or Saratov-45, this coil could be made in the form of a lattice welded to a metal sheet, but the tubes themselves remained copper.

The evaporator, located inside the freezer or refrigeration chamber, was also often made of copper tubes sealed into aluminum plates or consisting of a solid sheet with extruded channels. In old "crying" evaporators, copper formed the basis of the heat exchanger. When dismantling such units, it is important to act carefully so as not to crumble the aluminum plates if your goal is a clean copper tube.

⚠️ Attention: When dismantling an evaporator built into the wall of the refrigerator (foamed), there is a high risk of damaging the tube. In older models, it can be brittle due to age-related corrosion, so use sharp tools with caution.

To remove copper from the heat exchange circuit, you need to bite the tubes at the entrance and exit points of the housing. The length of the extracted material can vary from 5 to 10 meters depending on the model. In old ZIL and Saratov refrigerators, the weight of the copper circuit tubes can reach 1.5–2.5 kg, which is the main value of the unit for delivery.

Compressor: source of winding copper

If the heat exchanger is the “circulatory system,” then the compressor is the “heart” of the refrigerator. This is where the second most important part of the non-ferrous metal is concentrated. An old-style compressor is a sealed casing with an electric motor inside. The bulk of the copper here is the motor stator winding.

In old Soviet compressors, such as the series FK, DH or ND, exclusively pure copper wire with enamel insulation was used to wind the coils. The weight of this copper can range from 300 grams to 1.2 kg, depending on the power of the motor. Modern compressors often use aluminum or its alloys, which significantly reduces their value for non-ferrous metal collectors.

To get to the winding, you need to open the sealed casing. This is done using a grinder or a hacksaw, cutting off the top of the “pear” or passing along the weld. Inside you will find the pumping mechanism itself and the electric motor. The copper winding is located on the stator - the stationary part of the engine, consisting of metal plates.

• 🔴 Pure copper: The wire has a characteristic red color on the cut and a flexible structure.
• ⚪ Aluminium: Silver-colored wire, stiffer and lighter, often found in Chinese compressors 2000s.
• 🟡 Brass: An alloy of copper and zinc, has a more yellow tint, less often used in windings, more often in valves.

When removing copper from a compressor, a dilemma often arises: to remove the entire winding or burn the insulation. Incineration (scorching) allows the metal to be released faster, but up to 3-5% of the weight is lost due to surface oxidation, and the copper itself becomes burnt out (lower grade). Mechanical cleaning or delivery in the form of a “motor” (motor assembly) may be more profitable.

Pipelines and connecting elements

In addition to the main heat exchangers, copper in old refrigerators was widely used for connecting pipes and capillary tubes. The capillary tube is a thin copper conductor that provides throttling of the refrigerant and a pressure drop in front of the evaporator. Its diameter is a fraction of a millimeter, but the length can reach several meters.

Unlike modern models, where the capillary can be glued to the main pipe or hidden in insulation, in old refrigerators it often ran openly along the body or was accessible for visual inspection after removing the back panel. This element requires delicate handling, since if handled carelessly it breaks and is lost in the thermal insulation.

It is also worth paying attention to filter dryers. Although their body is most often made of copper or brass, the inside contains zeolite or silica gel, which are not non-ferrous metals. However, the weight of the filter housing itself (usually a small cylinder) adds grams to the total scrap weight. In some older models, for example, in industrial or large two-chamber Saratov, there were copper shut-off valves and fittings.

It is important to distinguish between the materials of the tubes. During the transition period (late 80s - early 90s), manufacturers could use copper-plated steel tube (copper-plated steel). You can check this with a magnet: copper and brass are not magnetic, steel is. If the magnet sticks to the tube, even weakly, it means it is ferromagnetic, and the price for such scrap will be much lower.

How to distinguish brass from copper?

Brass has a paler, yellowish tint, while copper is a rich red-orange. In addition, brass is harder and produces a louder sound when struck, while copper produces a duller sound.

Electrical wiring and control components

The third, although less voluminous, part of the copper is hidden in the electrical circuit of the refrigerator. Older models did not have complex electronic control boards, but had high-quality wiring. The cables going from the outlet to the compressor, from the thermostat to the engine, as well as internal connections, are made of copper.

The thermostat (thermostat) is an important component, which also contains copper. The thermostat sensing element is a capillary tube filled with freon or gas, which is often made of copper or brass. It runs along the evaporator and reacts to temperature changes. When dismantling the thermostat, this thin “tail” should be removed completely.

The starting and protective relays mounted on the compressor casing also contain small amounts of copper in their contact groups and coils. Although the weight of copper here is measured in grams, when mass recycling dozens of refrigerators, these parts matter. In old type relays RTK or R-1 the contacts were often silver-plated, but the base remained copper.

Differences in models: USSR versus Import

Geography of refrigerator production directly affects the quantity and the quality of non-ferrous metals inside. Soviet industry worked according to a planned economy, where the shortage of copper was compensated by the durability of products, but copper was still used willingly in everyday life. Imported equipment, even old, could have its own characteristics.

Refrigerators Indesit, Ariston or Beko 90s have often already switched to aluminum evaporators and steel condensers with copper coating to reduce costs. However, the compressors in them, especially if they are brands Embraco or Danfoss that period, could still contain full-fledged copper windings. European models tended to be more compact, which reduced the overall length of the circuit tubes.

In contrast, old Chinese models or equipment from Eastern European countries (GDR, Poland, Czech Republic) could be very similar to the Soviet one in design. For example, refrigerators Gorenje or Zanussi early series often had a classic copper “filling”. The key indicator remains the year of manufacture: the older the unit (before 1990), the higher the likelihood of the presence of pure copper.

Safety and environmental aspects

Disassembling an old refrigerator is not only a search for copper, but also working with potentially hazardous substances. Refrigerant circulates inside the system. In older models, this is most often freon R12 (dichlorodifluoromethane). Although it itself is not toxic in small doses, upon contact with an open flame (for example, when burning wire insulation or cutting with a grinder), it can decompose to form phosgene, a chemical warfare agent.

In addition, the thermal insulation of old refrigerators (polyurethane foam) may contain vapors of ammonia or other substances that are released when the structure is destroyed polystyrene foam Therefore, work on sawing the housing or breaking out internal panels should only be carried out outdoors or in a well-ventilated area using a respirator.

⚠️ Warning: Never attempt to open the compressor or cut pressure tubes without first piercing it in a safe place. Residual pressure can spray oil or refrigerant into your eyes.

It is also worth remembering about the oil in the compressor. It is technical, often mineral, and cannot be discharged into the sewer or onto the soil. Collect used oil in an airtight container and take it to a hazardous waste collection point. When working with an angle grinder, use safety glasses, as springs and small parts of the compressor can fly off at high speed.

Economic feasibility of removal

Is the gamble worth it? To answer this question, you need to compare the time and effort involved with the current value of the scrap. Copper is an expensive metal, but its quantity in one refrigerator is finite. If you disassemble one unit for fun or for the sake of 2-3 kilograms of metal, that’s one thing. If we are talking about business, a production line and mechanization are required.

The greatest value is “burnt” copper (winding) and lump copper (tubes). A mixture of copper with aluminum or steel (bimetal) is estimated to be much cheaper, sometimes at the price of ferrous scrap. So sorting is a key step. Separating copper tubing from steel fixtures and aluminum plates increases profits.

In conclusion, old refrigerators remain one of the few available sources of "urban ore." Knowing where copper is located not only allows you to make money, but also contributes to the recycling of resources, preventing equipment from ending up in landfills. However, the approach must be rational: consider the cost of tools, time and safety.

Approximately how much copper can be obtained from one old refrigerator?

On average, from a Soviet refrigerator (for example, "ZIL" or "Saratov") you can get from 1.5 to 3.5 kg of copper, depending on the model and year of manufacture. Of these, about 1-2 kg are for the condenser and evaporator tubes, and 0.5-1.2 kg for the compressor windings. Imported models may contain less copper, sometimes up to 1 kg.

Is it possible to hand over an entire refrigerator without disassembling it?

Yes, many scrap metal collection points accept entire refrigerators, but evaluate them as ferrous scrap (steel) with a small coefficient for the presence of non-ferrous metals. Independent disassembly and sorting of copper allows you to earn 3-5 times more money, but it requires time and tools.

Is it harmful to burn insulation from copper wires?

Yes, it is harmful both environmentally and for the quality of the metal. When insulation (plastic, rubber) burns, toxic substances are released. In addition, copper oxidizes, losing weight and becoming a low-grade burnt metal. Mechanical cleaning is preferable, although more labor-intensive.

Where exactly is copper located in the compressor?

Copper is located inside the sealed compressor casing, on the stator of the electric motor. This is the winding of the coils that creates a magnetic field to rotate the rotor. To get to it, you need to cut the compressor housing.