How to seal the heat exchanger in the gas column. How to solder a geyser: copper, brass heat exchanger (radiator)

During the operation of geysers, a leak often appears, which can be completely eliminated on your own. If you do not want to pay the master and know how to handle a soldering iron, then you can solder the column yourself by closing the resulting micro-holes.

Heat exchanger (radiator)

The most common cause of gas column leakage is damage to the copper heat exchanger. This is usually due to the low quality of the copper from which this part is made. In places where impurities are present, the walls of the heat exchanger oxidize over time, which leads to a leak.

Necessary tools and materials

To solder the column with your own hands, prepare:

• Soldering iron or gas burner.
• Fine-grained sandpaper or metal brush.
• Solder. For copper parts, use wire POS-61, which is an alloy of lead and tin.
• Rag.

How to solder with a soldering iron

The easiest way to solder a copper heat exchanger is to use a soldering iron.

However, its use has its limitations:

• You can use a soldering iron only with minimal damage to the heat exchanger.
• You will be able to solder only a thin-walled element with this tool.

Before soldering, the column must be drained of water. Also, for this work, a certain preparation of the surface must be carried out, which has acquired a greenish tint at the place of oxidation. Using sandpaper or a metal brush, sand the surface to remove any bumps or burrs. After wiping everything dry with a rag, carefully cover the heat exchanger in the right place with special solder, and then use a soldering iron, making sure that the solder evenly fills the damaged area.

How to solder with a gas burner

If your column has a massive heat exchanger with high thermal conductivity, it is recommended to solder it with a burner. Preparatory work in this case will not differ from soldering with a soldering iron - the surface must be thoroughly cleaned, even and dry. Next, soldering is carried out with a propane torch, which creates a contact flame with a temperature of up to 2500.

The following video clearly shows the entire soldering process using a gas burner.

Warranty period (three years) NEVA LUX-5013 worked flawlessly, and in the fourth year of operation, water began to drip from it. The hope that one of the gaskets was worn out did not materialize. When the casing was removed from the geyser, a fistula was found in the heat exchanger, from which water spouted.

After discovering the fistula, the first desire was to replace the gas column heat exchanger with a new one, but when I found out that its cost was 1/3 of the cost of a new column, I decided to try to repair the gas column heat exchanger on my own, solder it with a soldering iron. I reasoned as follows: water flows through the heat exchanger tube, the temperature of which, when heated, cannot exceed 100 ° C. Solder melting point, depending on the brand, is about 200˚С. Consequently, the solder will not melt and the solder will seal the leak securely. Repair of the gas column heat exchanger was a success.

Communication with sellers of spare parts for gas water heaters and acquaintances identified the existing problem of water leakage in heat exchangers, both in gas water heaters of domestic and foreign manufacturers. As it turned out, the service life of gas column heat exchangers is mainly due to the method of water disinfection during purification in the city water supply system.

Currently, chlorine or its dioxide is mainly used to disinfect tap water. Water containing chlorine, passing through the copper tube of the heat exchanger, heats up during the operation of the gas column, and, as is known from chemistry, when heated, chlorine begins to react with copper, forming copper chloride. Thus, the tube is destroyed from the inside, which leads to the appearance of fistulas. In cities where water disinfection at treatment plants is carried out by ozonation, fistulas in the heat exchangers of flowing gas and electric water heaters practically do not appear.

It is also worth noting that at present, manufacturers have begun to install copper tubes with thinner walls and made of lower quality copper in heat exchangers. This is also one of the factors that reduce the service life of heat exchangers.

if the fistula is in a place accessible for soldering

Before starting soldering, it is necessary to drain the water from the heat exchanger, otherwise the water will remove heat, and it will be impossible to warm up the soldering place to the required temperature. To do this, open the hot water tap in the sink or sink and unscrew the union nut from the cold water supply pipe of the geyser. Since the column is at a level above the tap, most of the water will drain, but not all. To remove residue, I use a purge. This can be done with a compressor, vacuum cleaner or mouth. When blowing by mouth, you can use a flexible hose from a shower head. One of the union nuts of the flexible hose is screwed onto the thread of the water supply pipe of the heat exchanger through the gasket, and the heat exchanger pipe is blown through the mouth through the other end of the flexible hose. The remaining water is drained through the tap, and you can start repairing the heat exchanger.

The soldering itself is not difficult. If you do not have experience with a soldering iron, you can familiarize yourself with the soldering technology on the site page "How to solder with a soldering iron". With fine sandpaper, clean the location of the fistula from oxides. As a rule, copper oxidizes in this place and a greenish spot forms (it is clearly visible in the photo above). After cleaning, wipe the place with a cloth soaked in solvent to remove grease and dust. Tin with any solder, for example POS-61, (melting temperature not lower than 180 ° C) with a soldering iron with a power of at least 100 watts.

Rosin can be used as a flux, and the one with which violin bows are rubbed is also suitable. If there is no rosin, you can successfully use aspirin tablets (sold in pharmacies in the form of tablets called "acetylsalicylic acid"). A wonderful flux, I use it all the time in cases where it is impossible to clean. For example, when tinning stranded wires. Color the tablet and sprinkle small crumbs on the place of tinning, or rub the tablet on the heated surface. If during tinning the solder does not spread, but lays down in a loose layer, then the place of soldering is not warm enough. In this case, you can additionally warm up with another 40 W soldering iron, building hair dryer or iron, applying it next to the soldering point.

When the solder has evenly covered the required surface with a thin layer, you need to build it up to a thickness of 1-2 mm. The fistula on the heat exchanger has been eliminated and will never show itself again.

Now carefully inspect the gas column heat exchanger tube along its entire length. If you find a green spot, then there is a high probability that there is a micro-hole in this place that allows water to pass through. It is necessary to clean the tube with fine sandpaper to a shine and see if there is a small black dot. If there is, then be sure to tin and solder. Otherwise, after a couple of months, you will again have to do repairs.

How to solder a gas column radiator,
if the fistula is in a place inaccessible for soldering

If the place of water leakage occurred on the wall of the heat exchanger adjacent to the base of the geyser, then repair of the heat exchanger by soldering in place is not possible, and it must be removed from the geyser. The designers of NEVA LUX-5013 "tried". To remove the heat exchanger for repair, it is required to disassemble almost the entire gas column and, most unpleasantly, disconnect the gas pipe. I did not want to mess with gas pipes, as it is dangerous.

The removal of the heat exchanger for repair was prevented by an umbrella for the removal of gas combustion products, fixed with four aluminum rivets to the base of the gas column. I had to drill these rivets with an electric drill, remove the umbrella, and only then it became possible to remove the heat exchanger. During assembly, instead of rivets, the umbrella was fixed to the base with two M4 screws. If the wall does not interfere, then you can fix the umbrella with self-tapping screws.

Further, the repair of the gas column was carried out according to the above technology. Over the past two years, I had to repair the heat exchanger by sealing the fistulas five times. The last time the water began to flow from the side adjacent to the wall of the heat exchanger, and I decided to buy a new one, which I did. I am going to repair the old heat exchanger of the geyser, I will zaluzh and solder the tube along the entire length. Photo of the view of the heat exchanger from the side of attachment to the base.

When buying a heat exchanger for a geyser, I was surprised to find that they gave me not a new one, but an already repaired one. On the tube of the heat exchanger there was one of the same soldering, as I myself did when repairing my old heat exchanger. As a result, of the four available in the store, only one heat exchanger was not soldered. It turns out that the repaired heat exchangers that failed during the warranty period are shipped for spare parts. Fistulas are soldered in them and sold again. The warranty period for the heat exchanger is only 1 month. It turns out that in a few months you will have to repair the gas column again!

If you have to buy a heat exchanger for a geyser, carefully inspect it. If soldering is found, it is better to refuse the purchase. In the event of a replacement of a heat exchanger in a geyser under warranty, make sure that you install not a repaired heat exchanger that was in operation, but a new one.

Repair of a replaced gas column heat exchanger

For almost three years, the NEVA LUX-5013 gas water heater worked properly after replacing the heat exchanger, but happiness did not last forever, and suddenly water began to drip from it. I had to redo the repair.

Removing the casing confirmed my fears: a green spot appeared on the outside of the heat exchanger tube, but it was dry, and the fistula from which water oozed was on the side inaccessible for inspection and soldering. I had to remove the heat exchanger for repair.

When looking for a fistula on the back of the removed heat exchanger, a problem arose. The fistula was at the top of the heat exchanger tube and water oozed from it and flowed along all the tubes below. As a result, all the turns of the tube below the fistula turned green on top and were wet. Whether this was a single fistula or there were several, it was impossible to determine.

After the green coating had dried, it was removed from the surface of the heat exchanger using fine sandpaper. An external examination of the heat exchanger tube did not reveal blackened dots. To search for leaks, it was necessary to pressure test the heat exchanger under water pressure.

To supply water to the heat exchanger, the above-mentioned flexible hose from the shower head was used. One end of it was connected through a gasket to the water pipe for supplying water to the gas column (in the photo on the left), the second was screwed to one of the ends of the heat exchanger tube (in the photo in the center). The other end of the heat exchanger tube was plugged with a water tap.

As soon as the tap for supplying water to the geyser was opened, drops of water immediately appeared in the supposed places of fistulas. The rest of the tube surface remained dry.

Before soldering the fistulas, it is necessary to disconnect the flexible hose from the water supply network, open the plug valve and drain all the water from the heat exchanger by blowing it out. If this is not done, then the water will not allow the soldering place to be heated to the desired temperature, and the fistula will not be able to be soldered.

For soldering the fistula, which was located on the bend of the heat exchanger tube, I used two soldering irons. One, whose power is 40 W, led the tube under the bend for its additional heating, and the second, with a hundred-watt, performed soldering.

I recently purchased a building hair dryer for the household, and soldered the fistula in a straight section, warming up the place of soldering them additionally. It turned out that soldering with a hairdryer is much more convenient, since copper warmed up faster and better. The soldering turned out to be more accurate. It’s a pity I didn’t try to solder the fistula without a soldering iron, using only a building hair dryer. The temperature of the air from the hair dryer is about 600 ° C, which should be enough to heat the heat exchanger tube to the melting temperature of the solder. I'll check it out next time I repair.

After repair, the place of the heat exchanger tube, where the fistula is located, is covered with a millimeter layer of solder, and the water path is reliably blocked. Repeated pressure testing of the heat exchanger showed the tightness of the tube. Now you can assemble the gas column. Water will no longer drip.

I bring to your attention a short video on how to solder a gas column radiator.

It should be noted that with the help of the presented technology, it is possible to successfully repair not only gas column heat exchangers, but also copper heat exchangers and radiators of any other types of water heating and cooling devices, including copper radiators installed in cars.

Restoration of pipe flanges
geyser soldering

Somehow, two pieces of copper tubes with flanges caught my eye, on which American union nuts were put on. These parts are designed for the installation of water pipes from copper pipes.

When soldering the gas column heat exchanger, I remembered them, and the idea arose to restore the previously cracked copper pipeconnecting the heat exchanger outlet pipe to the hot water supply pipe, soldering new flanges to them, idly gathering dust on the shelf. The task was somewhat more complicated, since the available parts had a copper tube bent at a right angle. I had to take up a hacksaw for metal.

First, a part of the tube with a flange was sawn off in the place where the bend begins. Further, an expanded part of the tube was sawn off from the opposite end for further use as a connecting ring. If the tube were straight, then there would be no need to cut. The result was two pieces of tube about a centimeter long.

The next step is sawing off the cracked flange from the pipe. The sawn off piece of pipe should be equal in length to the piece of pipe with the flange prepared for repair in the previous step.

As you can see in the photo, the sawn-off piece of the gas column pipe at the place where the flange was formed had many cracks.

The photo shows parts prepared for soldering. On the left - the end of the gas column pipe, on the right - a new flange with a union nut, in the middle - a connecting ring.

Before soldering, you need to check how the prepared parts fit together. The tubes of the branch pipe should enter the ring easily, with a small gap.

The mating surfaces of the tubes and the ring before soldering must first be cleaned with fine sandpaper to remove the oxide layer. It is convenient to clean the ring inside by wrapping a round rod with sandpaper, for example, the handle of a small screwdriver. Next, the cleaned surfaces must be tinned with a thin layer of POS-61 tin-lead solder using a soldering iron with a power of 60-100 watts. As a flux, it is best to use acidic zinc chloride flux, in other words, hydrochloric acid slaked with zinc. Since copper parts are soldered, rosin or aspirin is also suitable.

When soldering, it must be ensured that the pipe joint is inside the ring approximately in the middle. If, after tinning, the tubes do not want to enter the ring, then you need to heat them up with a soldering iron, the solder will melt and the tubes will enter. Do not forget to put a cap nut on the tube before soldering the pipe.

After the tubes are articulated, all that remains is to fill the gap with molten solder. As you can see in the photo, it turned out to be a completely hermetic and mechanically strong connection. The branch pipe is repaired, and you can install it in place in the gas column, it will serve no worse than a new one.

The check showed the tightness of the pipe at the place of soldering, but a leak occurred at its other end, for the same reason a microcrack appeared. I had to repair the other end of the pipe in the same way. The geyser has been working with a repaired pipe for more than a year. No water leaks were observed.

Using this technology, it is possible to restore the tightness of not only copper and brass tubes, but also stainless steel and iron tubes. The technology is applicable not only for the repair of gas water heaters, but also for the repair of other devices and machines, including cars.

Connecting the exhaust pipe
to gas column umbrella

To repair the heat exchanger, it is necessary to dismantle the exhaust pipe. When installing this pipe in place, it is necessary to ensure the tightness of its connection with the gas column umbrella.

Sealing even a large gap up to a centimeter is easy to perform using asbestos soaked in water. This is a heat-resistant material that is produced in the form of sheets. In water, asbestos sags like cardboard, and is a soft mass that is well molded. After drying, the asbestos becomes quite hard and dense again. Asbestos can be reused. It is enough to soak the extracted pieces in water.

Knowledge of the basic elements of the gas column device is the key to the safe operation of the water heater, as well as the ability to carry out repairs (if necessary) with your own hands.

This is also important in a situation where you entrusted repair work to an outsider. If you understand your column, you will never be deceived, and you will not become a victim of "rip off" money.

The heat exchanger for the geyser is, without exaggeration, the most important part of the system. This is due to the fact that the heating of water occurs in it. Knowledge of the device, the principle of operation and the types of heat exchanger allows you to choose the most successful version of the geyser.

And considering the issue of the cost of this spare part will allow you to understand the choice of buying a heat exchanger for a geyser, or prefer buying a new water heater.

1 Heat exchanger device and principle of operation

The heat exchanger, or as it is also called the radiator, plays the main role in the design of the gas column. We will analyze the principle of operation. For example, the heat exchanger for the Neva gas column is a metal box structure, into which the thermal energy generated from the gas in the combustion chamber enters, previously.

Around this box there are special pipes through which water circulates when the water tap is turned. It is these two interrelated processes that make cold water hot, which in turn enters our system. The location of the curl pipes and their number is differentiated depending on the model.

The heat exchanger for the Electrolux geyser has spiral tubes, while the heat exchanger for the Bosch geyser has pipes that are made in the form of an oval.

Heat exchanger 275 for geysers is the following structural elements:

• A metal box, the walls of which have an optimal thickness so that the device has good heat dissipation, but at the same time, a small degree of wear and tear under constant exposure to temperature;
• Gas column branch pipe, together with a flange, a connecting ring and a nut;
• Thermal energy inlet and cold water inlet;
• Pipes for circulating water through a heat exchanger for a gas water heater, as well as an outlet pipe for discharging thermal water further through the system.

Recently, manufacturers, in order to save money, make the walls of the heat exchanger thinner than usual. According to the reviews, the heat exchanger for the Neva 3208 geyser had such a drawback, as well as the heat exchanger for the oasis geyser, on the 2012 models. Therefore, pay attention to all the opinions of buyers, on the Internet, before buying a water heater.

The device of most models, popular manufacturers such as the heat exchanger for the gas column Neva Lux 5514, or the heat exchanger for the gas column AEG have a reliable design.

At the same time, such heat exchangers become clogged over time. This is also due to the influence of the negative impact of chlorine on the walls of the heat exchanger, as well as stagnation in the water device. Therefore, if you notice that the water temperature or its pressure is decreasing, pay attention to the cleaning procedure, or contact a specialist for help.

2 Types of heat exchangers depending on the type of column

On water heaters that are on the market today, there are two main types of heat exchanger, depending on the metal used:

Copper heat exchanger for a geyser. Such a heat exchanger is used most often, for example, a heat exchanger for a gas column Neva Lux, as well as a heat exchanger for a gas column Neva 4513. Although such a heat exchanger has a slightly higher cost, it has a number of positive characteristics.

Among them: fast heating of circulating water (due to high heat transfer), good resistance to corrosive processes. At the same time, there is also the main drawback - a large weight (from 2.5 to 4 kg), which of course reduces the transportability of the entire water heater. It is also important to note the fact that in the presence of a percentage of impurities of other cheap metals, the degree of uniformity of heating the walls of the heat exchanger proportionally worsens (different metals have different levels of heat transfer). Which in turn becomes the main cause of structural failure;

Steel heat exchanger for a geyser. It is also a fairly common variety, among the representatives there is a heat exchanger for the Neva 4510 geyser, and a heat exchanger for the Vaillant geyser.

The radiator made from steel has a lower cost, higher heat resistance and light weight. Among the disadvantages are low heat transfer, and worse corrosion resistance (especially if the heat exchanger walls are thinner than necessary).

Also, when choosing a duct heater for a geyser, you should pay attention to the soldering technique used by the manufacturer. Most heat exchangers (especially domestic ones) are soldered using hard copper-phosphorus solder, while on expensive models progressive ultrasonic soldering is used. Thanks to the latter, the service life of the radiator is increased many times, due to the optimal heating of all parts, to the same extent.

2.1 Prices for heat exchangers

Before you buy a radiator for a geyser, you should analyze the cost and take into account the possibility of repairing a problematic heat exchanger, take into account the price of a new device, as well as the price of a new geyser.

The cost of the heat exchanger directly depends on the country of manufacture, and the material of the spare part. You can buy a heat exchanger for the Neva gas column in the region of 2500 - 4 thousand rubles.

Original imported parts made of copper (heat exchanger for Ariston gas column) are differentiated in the range from 3000 to 6000 rubles. It is also necessary to take into account the cost of replacing the old heat exchanger with a new one, usually from 1000 rubles.

On the other hand, the possibility of restoring an old heat exchanger depends on the degree of damage. Often people buy a new radiator without understanding it, but in the end it turns out that it was enough to clean it. Therefore, the heat exchanger for the Electrolux geyser should be disassembled and checked.

As a rule, minimal leakage means that radiator repair can extend its life from perhaps 1 month to several years. And given the fact that the price of the original analogue of the heat exchanger is equal to a third, and sometimes half the price of a new gas column, its repair becomes a mandatory step.

An important question is also where to buy a heat exchanger for a geyser. You should choose an official representative of the manufacturer, or certified points of sale, so you protect yourself from buying a low-quality fake. Remember also that when making a deal, first inspect the radiator for traces of dirty soldering, as sometimes sellers pass off a repaired product as a new one.

2.2 How to replace the heat exchanger in the gas column NEVA - video

Warranty period (three years) NEVA LUX-5013 worked flawlessly, and in the fourth year of operation, water began to drip from it. The hope that one of the gaskets was worn out did not materialize. When the casing was removed from the geyser, a fistula was found in the heat exchanger, from which water spouted.

After discovering the fistula, the first desire was to replace the gas column heat exchanger with a new one, but when I found out that its cost was 1/3 of the cost of a new column, I decided to try to repair the gas column heat exchanger on my own, solder it with a soldering iron. I reasoned as follows: water flows through the heat exchanger tube, the temperature of which, when heated, cannot exceed 100 ° C. Solder melting point, depending on the brand, is about 200˚С. Consequently, the solder will not melt and the solder will seal the leak securely. Repair of the gas column heat exchanger was a success.

Communication with sellers of spare parts for gas water heaters and acquaintances identified the existing problem of water leakage in heat exchangers, both in gas water heaters of domestic and foreign manufacturers. As it turned out, the service life of gas column heat exchangers is mainly due to the method of water disinfection during purification in the city water supply system.

Currently, chlorine or its dioxide is mainly used to disinfect tap water. Water containing chlorine, passing through the copper tube of the heat exchanger, heats up during the operation of the gas column, and, as is known from chemistry, when heated, chlorine begins to react with copper, forming copper chloride. Thus, the tube is destroyed from the inside, which leads to the appearance of fistulas. In cities where water disinfection at treatment plants is carried out by ozonation, fistulas in the heat exchangers of flowing gas and electric water heaters practically do not appear.

It is also worth noting that at present, manufacturers have begun to install copper tubes with thinner walls and made of lower quality copper in heat exchangers. This is also one of the factors that reduce the service life of heat exchangers.

if the fistula is in a place accessible for soldering

Before starting soldering, it is necessary to drain the water from the heat exchanger, otherwise the water will remove heat, and it will be impossible to warm up the soldering place to the required temperature. To do this, open the hot water tap in the sink or sink and unscrew the union nut from the cold water supply pipe of the geyser. Since the column is at a level above the tap, most of the water will drain, but not all. To remove residue, I use a purge. This can be done with a compressor, vacuum cleaner or mouth. When blowing by mouth, you can use a flexible hose from a shower head. One of the union nuts of the flexible hose is screwed onto the thread of the water supply pipe of the heat exchanger through the gasket, and the heat exchanger pipe is blown through the mouth through the other end of the flexible hose. The remaining water is drained through the tap, and you can start repairing the heat exchanger.

The soldering itself is not difficult. If you do not have experience with a soldering iron, you can familiarize yourself with the soldering technology on the site page "How to solder with a soldering iron". With fine sandpaper, clean the location of the fistula from oxides. As a rule, copper oxidizes in this place and a greenish spot forms (it is clearly visible in the photo above). After cleaning, wipe the place with a cloth soaked in solvent to remove grease and dust. Tin with any solder, for example POS-61, (melting temperature not lower than 180 ° C) with a soldering iron with a power of at least 100 watts.

Rosin can be used as a flux, and the one with which violin bows are rubbed is also suitable. If there is no rosin, you can successfully use aspirin tablets (sold in pharmacies in the form of tablets called "acetylsalicylic acid"). A wonderful flux, I use it all the time in cases where it is impossible to clean. For example, when tinning stranded wires. Color the tablet and sprinkle small crumbs on the place of tinning, or rub the tablet on the heated surface. If during tinning the solder does not spread, but lays down in a loose layer, then the place of soldering is not warm enough. In this case, you can additionally warm up with another 40 W soldering iron, building hair dryer or iron, applying it next to the soldering point.

When the solder has evenly covered the required surface with a thin layer, you need to build it up to a thickness of 1-2 mm. The fistula on the heat exchanger has been eliminated and will never show itself again.

Now carefully inspect the gas column heat exchanger tube along its entire length. If you find a green spot, then there is a high probability that there is a micro-hole in this place that allows water to pass through. It is necessary to clean the tube with fine sandpaper to a shine and see if there is a small black dot. If there is, then be sure to tin and solder. Otherwise, after a couple of months, you will again have to do repairs.

How to solder a gas column radiator,
if the fistula is in a place inaccessible for soldering

If the place of water leakage occurred on the wall of the heat exchanger adjacent to the base of the geyser, then repair of the heat exchanger by soldering in place is not possible, and it must be removed from the geyser. The designers of NEVA LUX-5013 "tried". To remove the heat exchanger for repair, it is required to disassemble almost the entire gas column and, most unpleasantly, disconnect the gas pipe. I did not want to mess with gas pipes, as it is dangerous.

The removal of the heat exchanger for repair was prevented by an umbrella for the removal of gas combustion products, fixed with four aluminum rivets to the base of the gas column. I had to drill these rivets with an electric drill, remove the umbrella, and only then it became possible to remove the heat exchanger. During assembly, instead of rivets, the umbrella was fixed to the base with two M4 screws. If the wall does not interfere, then you can fix the umbrella with self-tapping screws.

Further, the repair of the gas column was carried out according to the above technology. Over the past two years, I had to repair the heat exchanger by sealing the fistulas five times. The last time the water began to flow from the side adjacent to the wall of the heat exchanger, and I decided to buy a new one, which I did. I am going to repair the old heat exchanger of the geyser, I will zaluzh and solder the tube along the entire length. Photo of the view of the heat exchanger from the side of attachment to the base.

When buying a heat exchanger for a geyser, I was surprised to find that they gave me not a new one, but an already repaired one. On the tube of the heat exchanger there was one of the same soldering, as I myself did when repairing my old heat exchanger. As a result, of the four available in the store, only one heat exchanger was not soldered. It turns out that the repaired heat exchangers that failed during the warranty period are shipped for spare parts. Fistulas are soldered in them and sold again. The warranty period for the heat exchanger is only 1 month. It turns out that in a few months you will have to repair the gas column again!

If you have to buy a heat exchanger for a geyser, carefully inspect it. If soldering is found, it is better to refuse the purchase. In the event of a replacement of a heat exchanger in a geyser under warranty, make sure that you install not a repaired heat exchanger that was in operation, but a new one.

Repair of a replaced gas column heat exchanger

For almost three years, the NEVA LUX-5013 gas water heater worked properly after replacing the heat exchanger, but happiness did not last forever, and suddenly water began to drip from it. I had to redo the repair.

Removing the casing confirmed my fears: a green spot appeared on the outside of the heat exchanger tube, but it was dry, and the fistula from which water oozed was on the side inaccessible for inspection and soldering. I had to remove the heat exchanger for repair.

When looking for a fistula on the back of the removed heat exchanger, a problem arose. The fistula was at the top of the heat exchanger tube and water oozed from it and flowed along all the tubes below. As a result, all the turns of the tube below the fistula turned green on top and were wet. Whether this was a single fistula or there were several, it was impossible to determine.

After the green coating had dried, it was removed from the surface of the heat exchanger using fine sandpaper. An external examination of the heat exchanger tube did not reveal blackened dots. To search for leaks, it was necessary to pressure test the heat exchanger under water pressure.

To supply water to the heat exchanger, the above-mentioned flexible hose from the shower head was used. One end of it was connected through a gasket to the water pipe for supplying water to the gas column (in the photo on the left), the second was screwed to one of the ends of the heat exchanger tube (in the photo in the center). The other end of the heat exchanger tube was plugged with a water tap.

As soon as the tap for supplying water to the geyser was opened, drops of water immediately appeared in the supposed places of fistulas. The rest of the tube surface remained dry.

Before soldering the fistulas, it is necessary to disconnect the flexible hose from the water supply network, open the plug valve and drain all the water from the heat exchanger by blowing it out. If this is not done, then the water will not allow the soldering place to be heated to the desired temperature, and the fistula will not be able to be soldered.

For soldering the fistula, which was located on the bend of the heat exchanger tube, I used two soldering irons. One, whose power is 40 W, led the tube under the bend for its additional heating, and the second, with a hundred-watt, performed soldering.

I recently purchased a building hair dryer for the household, and soldered the fistula in a straight section, warming up the place of soldering them additionally. It turned out that soldering with a hairdryer is much more convenient, since copper warmed up faster and better. The soldering turned out to be more accurate. It’s a pity I didn’t try to solder the fistula without a soldering iron, using only a building hair dryer. The temperature of the air from the hair dryer is about 600 ° C, which should be enough to heat the heat exchanger tube to the melting temperature of the solder. I'll check it out next time I repair.

After repair, the place of the heat exchanger tube, where the fistula is located, is covered with a millimeter layer of solder, and the water path is reliably blocked. Repeated pressure testing of the heat exchanger showed the tightness of the tube. Now you can assemble the gas column. Water will no longer drip.

I bring to your attention a short video on how to solder a gas column radiator.

It should be noted that with the help of the presented technology, it is possible to successfully repair not only gas column heat exchangers, but also copper heat exchangers and radiators of any other types of water heating and cooling devices, including copper radiators installed in cars.

Restoration of pipe flanges
geyser soldering

Somehow, two pieces of copper tubes with flanges caught my eye, on which American union nuts were put on. These parts are designed for the installation of water pipes from copper pipes.

When soldering the gas column heat exchanger, I remembered them, and the idea arose to restore the previously cracked copper pipeconnecting the heat exchanger outlet pipe to the hot water supply pipe, soldering new flanges to them, idly gathering dust on the shelf. The task was somewhat more complicated, since the available parts had a copper tube bent at a right angle. I had to take up a hacksaw for metal.

First, a part of the tube with a flange was sawn off in the place where the bend begins. Further, an expanded part of the tube was sawn off from the opposite end for further use as a connecting ring. If the tube were straight, then there would be no need to cut. The result was two pieces of tube about a centimeter long.

The next step is sawing off the cracked flange from the pipe. The sawn off piece of pipe should be equal in length to the piece of pipe with the flange prepared for repair in the previous step.

As you can see in the photo, the sawn-off piece of the gas column pipe at the place where the flange was formed had many cracks.

The photo shows parts prepared for soldering. On the left - the end of the gas column pipe, on the right - a new flange with a union nut, in the middle - a connecting ring.

Before soldering, you need to check how the prepared parts fit together. The tubes of the branch pipe should enter the ring easily, with a small gap.

The mating surfaces of the tubes and the ring before soldering must first be cleaned with fine sandpaper to remove the oxide layer. It is convenient to clean the ring inside by wrapping a round rod with sandpaper, for example, the handle of a small screwdriver. Next, the cleaned surfaces must be tinned with a thin layer of POS-61 tin-lead solder using a soldering iron with a power of 60-100 watts. As a flux, it is best to use acidic zinc chloride flux, in other words, hydrochloric acid slaked with zinc. Since copper parts are soldered, rosin or aspirin is also suitable.

When soldering, it must be ensured that the pipe joint is inside the ring approximately in the middle. If, after tinning, the tubes do not want to enter the ring, then you need to heat them up with a soldering iron, the solder will melt and the tubes will enter. Do not forget to put a cap nut on the tube before soldering the pipe.

After the tubes are articulated, all that remains is to fill the gap with molten solder. As you can see in the photo, it turned out to be a completely hermetic and mechanically strong connection. The branch pipe is repaired, and you can install it in place in the gas column, it will serve no worse than a new one.

The check showed the tightness of the pipe at the place of soldering, but a leak occurred at its other end, for the same reason a microcrack appeared. I had to repair the other end of the pipe in the same way. The geyser has been working with a repaired pipe for more than a year. No water leaks were observed.

Using this technology, it is possible to restore the tightness of not only copper and brass tubes, but also stainless steel and iron tubes. The technology is applicable not only for the repair of gas water heaters, but also for the repair of other devices and machines, including cars.

Connecting the exhaust pipe
to gas column umbrella

To repair the heat exchanger, it is necessary to dismantle the exhaust pipe. When installing this pipe in place, it is necessary to ensure the tightness of its connection with the gas column umbrella.

Sealing even a large gap up to a centimeter is easy to perform using asbestos soaked in water. This is a heat-resistant material that is produced in the form of sheets. In water, asbestos sags like cardboard, and is a soft mass that is well molded. After drying, the asbestos becomes quite hard and dense again. Asbestos can be reused. It is enough to soak the extracted pieces in water.

A heat exchanger is one of the main devices in a gas heating apparatus, which is responsible for heating the coolant. In a geyser, the heat exchanger has a solid surface through which heat is transferred to the coolant. Due to the influence of various external factors, fistulas and ruptures may appear in the walls of the coolant, and the geyser may begin to flow. You can fix the problem yourself. How - read below.

A geyser is an affordable and reliable water heating equipment. But, due to poor-quality water and gas, the life of the gas column can be reduced significantly. In order not to change equipment every few years, you should understand how to repair it. So, most often, leaks of columns and insufficient heating of the coolant are associated with malfunctions of the heat exchanger. Troubleshooting can usually be done in two ways: cleaning or soldering the heat exchanger.

At the same time, in order to avoid situations dangerous to health and life, repair work should be carried out:

• After stopping the supply of water (or other coolant) and gas;
• On an empty apparatus (you must first drain the water from the gas column or remove any other coolant);
• In protective gloves, glasses, clothes (if we are talking about soldering).

If you decide to call a specialist to carry out repairs, choose only certified craftsmen with good reviews. At the same time, it will not be superfluous to independently understand the device of the gas column and how to repair equipment. After all, you may come across an unscrupulous worker who, seeing your incompetence, will “find” non-existent malfunctions for maximum financial benefit.

Soldering the gas column heat exchanger

Soldering of the gas equipment heat exchange device is performed when the element is depressurized. Most often, the appearance of fistulas in copper heat exchangers is associated with poor-quality, hard water. So, in most cities, today, water is disinfected with chlorine. When heated, the chlorine in the water reacts with copper (the heat exchanger material), forming copper chloride. As a result, the walls and tubes of the heat exchanger begin to collapse from the inside. Frozen water in the system, the presence of stray currents can also lead to the rupture of the walls of the heat exchanger.

There are three ways to solder the heat exchanger:

• using a soldering iron with a power of at least 100 watts;
• using a burner with a gas cylinder;
• cold welding.

Before applying solder, you should clean the surface of the radiator. It is necessary to process not only gaping fistulas, but also greenish spots on the surface of the heat exchanger, which signal thinning of the metal.

In order for the solder to spread well over the metal, it is better to use a copper flux paste for soldering.

You can replace it with more affordable rosin. On average, good soldering lasts six months. Grounding the dispenser can reduce the likelihood of new leaks. You can extend the life of the heat exchanger by installing a filter at the system inlet that purifies and softens the water.

How to remove the heat exchanger from the geyser

In some cases, for example, when a fistula or rupture is located on the wall of the heat exchanger, which is adjacent to the base of the gas equipment, the radiator must be removed for repair. In addition, the dismantling of the heat exchanger may be necessary if you decide to clean it.

In order to remove the heat exchanger from the gas water heater, you must:

1. Turn off the water and gas supply to the gas water heater;
2. Remove the switch handle and casing from the device by unscrewing the connecting screws with a Phillips screwdriver;
3. Disconnect the chimney;
4. Remove the overheating sensor from the upper metal element of the column;
5. Drill out the rivets holding the upper metal element from dismantling;
6. Remove the upper metal structure by moving your hand upwards;
7. Using a wrench, unscrew the nuts from the pipes to which the heat exchanger is attached;
8. Remove the heat exchanger towards the top.

If, after dismantling the device, you find that it cannot be repaired (for example, the heat exchanger burned out), then it will have to be replaced with a new one. At the same time, the issue of choice should be approached carefully. Often, heat exchangers in stores are recycled: after replacing the elements under warranty, the manufacturer repairs the failed heat exchange device and sends it for sale. Pay attention to the weight of the heat exchanger: sometimes, in order to reduce the cost of manufacturing a part, the manufacturer intentionally makes the walls of the element thinner. This significantly affects the life of the heat exchanger. How much does a quality device weigh? On average, at least 3 kg.

How to clean a gas column radiator

Among the regular maintenance measures for gas water heating equipment, cleaning of the heat exchanger occupies an important place. Cleaning should be done at least once a year. If your area has hard water with various impurities, then you can hold the event more often. In addition, cleaning is the first thing to do if the column has become worse at heating water for no apparent reason.

The best substance for cleaning the heat exchanger at home is citric acid.

Citric acid is available to everyone, effective and absolutely safe for metal. At the same time, the product does not emit carcinogenic substances and an unpleasant odor.

In order to clean the radiator with a “lemon” you need to:

1. Dissolve 100 grams of the substance in a liter of warm water;
2. Pour the resulting solution into the heat exchanger;
3. Lower the part into a container with a solution;
4. Wait 15-20 minutes;
5. Rinse the radiator with running water;
6. Wait for the part to dry.

You can use vinegar essence to clean the radiator. In this case, the cleaning algorithm should be left unchanged. You can rid the radiator of scale with the help of special tools (for example, antiscale SK-110A).

How does a gas column heat exchanger work (video)

The most efficient, affordable and economical domestic water heater today is a gas water heater. The equipment consists of a heat exchanger, an igniter and a main burner. The copper heat exchanger is most susceptible to wear: under the influence of hard water, the tubes of the element are clogged, and its walls are corroded. But, do not be upset: equipment repair can be done by yourself. And the above instructions and recommendations will help you with this!