To connect air conditioning tubes in apartments or offices, rolling is most often used. This method is simple, affordable and safe for equipment. But sometimes it is necessary to solder the tubes of the air conditioner.
If you have basic technical knowledge, you can replace or re-solder the copper pipe in the air conditioner yourself. Pipes are not included in the device’s package - they are bought at construction stores. A copper pipe with silver impurities is suitable, able to withstand temperature differences that occur during the operation of climate systems, and not subject to corrosion. Pipe materials withstand high pressure and are not deformed. The chemical composition allows you to save the surface layer for a long time, which allows the system to work without the need for repair.
Materials and equipment
The diameter of the pipe is selected based on the power of the device - the more powerful, the larger the diameter. The cost of the pipe is affected by its technical characteristics, brand of the manufacturer, and the characteristics of the metal. Do not save on pipes, since the service life and quality of the split system depend on this.
Soldering air conditioning tubes begins with the selection of the necessary tools and materials:
- Pipe cutter. This tool will allow you to well prepare the end of the part, which will be connected using solder.
- Pipe bender. To avoid creases and poor traffic, you need to use a special tool so that the diameter does not change, and at the same time, the pipe can be bent at an angle.
- Metal soldering iron, gas burner.
- Solder for brazing air conditioning copper pipes.
On the strength and tightness of soldering, surface cleanliness is of greater importance. But the type of solder needs to be selected correctly. Soldering is carried out with hard or soft solder.
Solders are divided into:
- copper phosphoric;
- silver ones.
To solder the aluminum tube of the air conditioner, two types of solder are used at once. For copper tubes, it is better to choose a solder with silver ions than phosphorus. This is due to the fragility of the phosphorus substance in the event that more than 10% nickel is in the alloy.
If cadmium is included in the solder, you need to take care of your health, since the fumes poison the body.
For a good connection of the tubes, a combustible mixture is selected. Check when turned on:
- If the torch is of medium size and uniform blue, this means that the gas-oxygen mixture is well balanced in composition. The metal will heat evenly.
- The pale blue color of the torch indicates that the mixture has more oxygen. This will oxidize the metal and a dark coating will appear on it.
When expanding the outer tube, the necessary gap is observed, into which the solder will flow. In the absence of such, the connection of the tubes will not be tight, and freon will leak under pressure in a matter of minutes.
How copper tubes are soldered - process and rules
Before connecting the air conditioner tubing, clean it with an emery or wire brush. Residues of grease, earth, paint impair adhesion of solder and metal.
The soldering of the tubes of the air conditioner is carried out by the flame of a gas burner. With an optimal gas mixture, the flame simultaneously cleans and heats the surfaces of the tubes, preparing them for connection.
To connect the tubes of the air conditioner by soldering, you must insert one tube into another at a length equal to or greater than the diameter of the tubes. The gap is from 0.025 cm to 0.125 cm.
The tubes are heated evenly by the burner. To solder penetrated into the gap, the temperature of the inner and outer must be the same.In this case, not only the place of the proposed welding is captured, but also a little further - by 7 centimeters in each direction.
The heated solder rod is lowered into the flux, a thin layer of which protects it from oxide. The smaller the flux layer, the better the soldering.
After it turned out to seal the tubes of the air conditioner, the remains of the flux are cleaned off.
Conditions that are observed when working:
- The burner must have a flame reduction function to control the heating process. The superheated tube is deformed and the end has to be sawed off.
- Flaring is carried out on the pipe, which lies towards the going freon, so that there is no friction and resistance in the place of soldering. For example: if freon goes on the left, then expand the right side of the tube and vice versa.
- Since some solders emit harmful gases during heating, provide ventilation or wear a respirator.
Low temperature soldering
The low-temperature mode of joining two metal parts implies heating of the main parts below 427 degrees, that is, below the melting temperature of the base metal. With this method, the metal is less oxidized, local heating can be achieved. Energy and materials are saved. The result is a neat, accurate junction.
Features of high temperature soldering
The melting temperature during high-temperature soldering is higher than 427 degrees, but lower than the melting temperature of the parts to be joined. The technology is different from low temperature. For vacuum brazing, use tin soft solder. High-temperature technologies are used for compounds that will subsequently work with high temperatures.
For independent performance of work, a sufficiently low-temperature regime is sufficient. The pipes are not supposed to have high freon temperatures, but the connection must be airtight to avoid refrigerant leakage during operation.
Air conditioner tube welding
The method of argon welding of air conditioning tubes is used for wear or deformation of aluminum tubes. Argon welding is used because heated aluminum is coated with an oxide film when interacting with oxygen. Argon prevents contact with oxygen and film formation.
The tube welding method is good for repairing car air conditioners.
