When the refrigerator stops freezing and diagnostics indicate a malfunction discharge unit, the owner is faced with the question of the possibility of restoration or exact replacement details. Disassembling a compressor is a complex technical process that requires not only specific tools, but also a deep understanding of the device sealed systems. Many craftsmen prefer to replace the entire unit, however, in some cases, for example, when the piston group is jammed or the valves break, opening the housing allows you to save an expensive unit.
Before you begin to physically impact the housing, you must clearly understand that standard refrigerator compressor is a sealed device. Inside there is a refrigerant under pressure and a special oil. Manufacturers initially they did not plan for the possibility of disassembly, so all connections were made by welding. Your task is to carefully break this tightness, preserving the integrity of the internal mechanisms, if the goal of the repair is to restore them. Ignoring safety rules when working with metal and electricity is unacceptable.
It should immediately be noted that the success of the operation directly depends on the type of malfunction. If the winding burns out electric motor, then disassembly often does not make sense, since rewinding at home is impossible or economically impractical. However, if the problem lies in the mechanical part, then access to the insides of the unit opens the way to solving the problem. Next, we will look in detail at how to properly organize the work process and what tools will be required for high-quality dismantling.
Necessary tools and preparation of the workplace
For high-quality disassembly of the compressor of an ordinary household refrigerator, you will need a set of tools that goes beyond the standard home master's first aid kits. The main tool will be angle grinder (grinder) with thin cutting discs for metal, since it is with this that you will have to cut off the weld seam of the body. A hammer, chisel or chisel will also be indispensable for carefully separating the casing halves after cutting. Do not forget to prepare a container for draining compressor oilas it will leak immediately after opening.
Safety is priority number one. You will need safety glasses to prevent metal shavings from getting into your eyes, and thick gloves. Since residual pressure or refrigerant vapor may remain inside the unit, work in a well-ventilated area. It will also be required multimeter for initial diagnostics of the windings before disassembly, to make sure that the electrical part is intact. If you plan to solder the unit back, you will need a torch and solder.
☑️ Preparing to disassemble the compressor
It is important to prepare the workplace: the table must be stable, and the surface must be protected from sparks and oil. Make sure in advance that you have solvent or Galosh gasoline for washing parts, since the insides of the compressor are usually covered with a layer of oily soot. Without cleanliness in the friction unit, reassembly can lead to rapid wear of parts.
Removing the compressor from the refrigeration unit
The first stage of work is removing the compressor from the general refrigerator system. The process begins by disconnecting the device from the power supply and moving it away from the wall. You need to gain access to the bottom of the housing where the motor-compressor is located. It is usually secured to the frame with four vibration isolating bushings or bolts. Before unscrewing the fasteners, it is necessary to bleed off the refrigerant if the system has not been previously damaged, although when completely replacing or repairing the compressor, the freon is often simply released (which is environmentally incorrect, but is often practiced during homemade repairs).
The next step is to disconnect the copper tubes. Use a pipe cutter or carefully cut them with side cutters, leaving enough length for future sealing. If the tubes are stuck, do not pull them with force, so as not to damage the discharge pipe. After freeing the copper lines, unscrew the mounting bolts or remove the spring clips. The unit can now be removed from the frame. Be careful: the compressor can weigh up to 10 kg, and the oil inside can spill out when tilted.
⚠️ Attention: Before starting any work, make sure that the capacitor in the start relay is discharged. Briefly closing the contacts with a screwdriver (after insulating the handle) will help avoid an unpleasant electric shock, even if the device is unplugged from the outlet.
After removing the compressor from the refrigerator frame, you need to remove the start relay and thermal protection. They are usually simply put on the contact group and secured with a metal bracket or plastic box. Carefully remove them, remembering or photographing the position of the contacts. This is important for subsequent diagnostics and assembly. Now you have a “naked” compressor in your hands, ready for opening.
Opening the sealed housing compressor
The most crucial moment is the violation of the integrity of the weld. The compressor housing consists of two stamped hemispheres, welded along the equator. Your task is to make a cut along this seam without touching the internal mechanisms. To do this, it is convenient to clamp the compressor in a vice through wooden blocks or place it on a stable surface. Turn on grinder and move the disk strictly along the line of the welded joint. The cutting depth should be minimal, just enough so that the metal begins to diverge.
Do not try to cut through the body the first time. Make a notch in a circle, then turn the unit over and continue on the other side. When the depth is sufficient (usually 1-2 mm), insert a flat-head screwdriver or chisel into the slot and carefully, with light blows of a hammer, try to separate the halves. If the seam is sawn correctly, the body will separate with a characteristic click. The main thing here is not to damage the stator and rotor, which are located inside.
After removing the top cover, you will see the internal structure: a stator with windings, a rotor (armature) with a crankshaft and a cylinder-piston group. Often the insides are filled with oil and covered with wear debris. Before touching the mechanisms, allow the oil to drain into a prepared container. Visually inspect the windings for blackening or a burning smell - these are signs interturn closure. If the windings are intact, you can proceed to further disassembly of the mechanical part.
What to do if the seam does not separate?
If the halves do not separate after cutting, do not use excessive force. There may be some jumpers left. Go through the problem areas with the grinder again, controlling the depth so as not to scratch the disk on the insides.
Disassembly of the mechanical part and diagnostics
The internal structure of the compressor is a precision mechanism. The piston moves in the cylinder with microscopic clearances, so any scratches or dust are fatal to the assembly. To remove the piston group, it is usually necessary to unscrew several bolts securing the cylinder to the stator housing, or carefully knock the shaft out of the bearings. Be careful: counterweights that cannot be bent may be installed on the shaft. eccentrics and counterweights that cannot be bent.
When removing the rotor from the stator, be careful not to damage the thin plates of the stator. If the compressor seizes, the reason often lies in piston scuffing or destruction of the plain bearings. In some models atmospheric compressors (although they are rare in refrigerators) or units with a separate cylinder-piston group, the piston or liners can be replaced. However, in most household models, the parts are not sold separately, and repairs boil down to cleaning and reassembling if the scuffs are minor.
Pay special attention to the valve plate. It is located on top of the cylinder and is pressed with bolts or rivets. This is where the thin valve reeds most often break, resulting in a lack of pressure. If the valve is intact, but the compressor does not pump, check the integrity of the gaskets. The use of old gaskets during assembly is unacceptable - they lose elasticity and leak.
| Component | Function | Typical malfunction | Elimination method |
|---|---|---|---|
| Piston group | Freon compression | Cylinder scuffing, ring wear | Replacing the group or honing |
| Valve plate | Adjusting the gas flow | Valve tongue burst | Replacing the plate |
| Electric motor | Shaft rotation | Breakage or short circuit of the winding | Rewinding (rarely) or replacement |
| Bearings | Support shaft | Output, backlash | Replacement of liners |
Washing parts and removing contaminants
After disassembly, you will see that the internal parts are covered with a dark coating. These are products of oil and freon decomposition, as well as metal shavings. For cleaning, use solvent 646, Galosh gasoline or specialized liquids for cleaning carburetors. It is strictly forbidden to use water or aggressive acids, which can cause corrosion. Flushing must be thorough, especially the oil supply channels and sliding bearings.
Pay special attention to the oil pump if it is designed in the form of a screw pair or an eccentric on the shaft. Clogging of channels with oil and wear products is a common cause of re-seizing after repair. Blow out all channels with compressed air. If you are planning to put the compressor back together, cleanliness is 90% of success. Even a grain of sand between the piston and cylinder will damage the unit after a few minutes of operation.
After washing, dry the parts. You can use a hair dryer, but do not overheat them. Make sure there is no moisture or solvent left in the motor windings as this may damage the insulation. Check the insulation resistance with a megohmmeter, if possible. At home, it is enough to make sure that the varnish coating of the wires is dry and free of visible damage.
⚠️ Attention: Old compressor oil contains acidic impurities. Do not pour it down the drain or onto the ground. Collect the waste in a closed container and hand it over to a hazardous waste collection point.
Assembling the compressor and sealing the housing
Assembly is carried out in the reverse order, but in compliance with the new requirements for tightness. Since the stock weld was cut off, you will have to recreate it. First, assemble the mechanical part, lubricating all rubbing surfaces with fresh compressor oil (for example, Frigen or equivalent). Install the piston group, check the ease of movement of the shaft. It should rotate by hand without jamming. compressor oil (for example, Frigen or equivalent). Install the piston group, check the ease of movement of the shaft. It should rotate by hand without jamming.
There are several methods for connecting the body halves. The most reliable method is welding, but brazing or using high-pressure sealants in combination with mechanical tightening is available at home. If you use sealantapply it to the grease-free edges, connect the halves and tighten tightly with clamps until completely dry. However, for full operation under freon pressure, it is better to weld the seam with argon or high-quality soldering around the perimeter.
After assembling the housing, it is necessary to replace the process pipe (if it was cut) and solder the fittings. The compressor is then vacuumed to remove moisture and air, and only then is it charged with freon and oil. Without evacuation, moisture will remain inside, which will freeze in the capillary and block the system. This is a critical stage that requires a pressure gauge station.
In conclusion, it is worth noting that disassembling a compressor is the job of experienced craftsmen with the appropriate equipment. If you do not have soldering skills, work with an angle grinder, or understand thermodynamic processes, it is easier and safer to buy a new compressor. However, if you decide to take this step, maintain cleanliness and accuracy.
Is it possible to disassemble a compressor without an angle grinder?
Theoretically, you can try to drill out welding points around the perimeter or use a hacksaw, but this is extremely labor-intensive and time-consuming. A grinder is the fastest and most effective way to control the depth of cut. Using a chisel to cut a seam without first cutting often leads to deformation of the body and damage to internal parts.
What kind of oil should be poured into a refrigerator compressor?
You should only use special synthetic or semi-synthetic oils for refrigeration compressors (for example, Polyol Ester). Conventional motor oil is absolutely not suitable, since it does not have the necessary chemical resistance to freons and can foam, causing water hammer and clogging of the system.
Why did the compressor jam after disassembly?
The most likely reason is the ingress of dust, dirt or lint during assembly. The compressor mechanism operates with micron gaps. Also, the reason may be overtightening of the bolts, deformation of the cylinder body, or the use of the wrong oil, which has solidified or formed a sediment.
Is it worth repairing the compressor of an inverter refrigerator?
Repairing inverter compressors at home is almost impossible. They have complex electronics built into the body and require precision balancing. Disassembling such a unit is almost guaranteed to lead to its final failure. Such units can only be replaced.