Do-it-yourself gas column heat exchanger repair: step-by-step instruction

click fraud protection

Instantaneous water heaters operating on natural gas are quite reliable devices that very rarely fail. Due to minor malfunctions that occur during the operation of the device, a large number of inconveniences may arise. In such cases, you should call the master at home or repair the heat exchanger of the gas column with your own hands in order to save money.

For the master, this procedure will not take even 5 minutes, but you still have to pay for the call. It is quite easy to fix a number of breakdowns that occur in this device. And how to detect a breakdown and independently repair a gas column, its heat exchanger and all its components - we will talk about all this in our article. We provide detailed instructions for soldering, providing the material with visual photos and useful videos.

The content of the article:

  • How does a water heater work and work?
  • Heat exchanger breakdown signs
  • Avoiding other column malfunctions
    • External inspection of the water heater
    • Troubleshooting inside the column
  • instagram viewer
  • Heat exchanger repair procedure
    • Stage # 1 - draining the water from the radiator
    • Stage # 2 - brazing copper pipes
    • Stage # 3 - search for defects after soldering
  • Conclusions and useful videos on the topic

How does a water heater work and work?

To learn how to repair a gas water heater, you must first understand how it works and how it works.

Aggregates can be of the following types:

  1. With an open combustion chamber or atmospheric.
  2. With a closed combustion chamber or turbocharged. They are also called inflatable.

The air required for combustion of the gas enters the atmospheric column from the environment in a natural way. It enters the device through the opening located at the bottom of the column. For the removal of combustion products, a natural draft chimney is installed.

Turbocharged or inflatable columns differ from atmospheric ones in one peculiarity: their combustion chamber is closed, and the built-in fan provides forced draft. Air inflow and its removal is carried out forcibly through a coaxial chimney (double-walled).

You can get acquainted with the device of a gas water heater in general terms by looking at the following illustration.

Structural elements of a gas column

The photo shows the device of a typical gas water heater. The design feature of this water heater is the piezo ignition of the burner. Also, batteries (or from a 220 V network), a hydraulic turbine can be used to ignite various models

Below will be presented the principle of operation of a modern gas burner with an automatic ignition system:

  1. The column starts working when the mixer tap is opened. The water flow passes through the water supply unit and the heat exchanger of the gas device.
  2. Inside the column housing is a water regulator membrane that pushes the stem under the pressure from the water. This allows the stem to compress the spring of the mechanical gas valve in the block so that the fuel can reach the burner itself.
  3. At this stage, the solenoid valve circuit closes, which occurs when the button is released by the stem microswitch. The valve provokes the launch of gas into a special tube, which is supplied. The gas flows to an already open spring valve.
  4. The impulse device is triggered. It delivers a discharge to the electrodes that are next to the burner. Sparks are formed, as a result of which ignition begins. This makes it possible to heat the water passing through the heat exchanger.

The electromagnetic circuit consists of 3 sensors that are connected in series. These include a draft sensor, overheating and flame sensor. When the last element of the chain fixes the fire, at this moment the formation of sparks ends.

We examined the principle of operation of the column in more detail in this material.

Igniter and flame sensor

Old gas water heaters had one contact and a constantly working igniter. Now they make devices with two electrodes that ignite the burner.

Heat exchanger breakdown signs

After you have learned in more detail about the principle of operation of the geyser, you can consider the important points necessary to successfully prevent damage to the radiator.

So, there are several conditions when it is necessary to repair a faulty gas column heat exchanger, since the unit itself begins to automatically turn off:

  • The flow of water ceases to occur and there is no pressure. In this case, the water regulator releases the push rod, which is the reason for the shutdown. microswitch.
  • The last element of the electromagnetic circuit, that is, the ionization sensor, ceases to “see” the flame. In this situation, the corresponding signal is not given, due to which the gas path is closed by the solenoid valve.
  • Draft ceases to form in the chimney. The electromagnet stops working, the electromagnetic circuit is broken and the fuel supply is no longer present.
  • The overheating sensor stops functioning. This component of the circuit is installed directly on the heat exchanger.

After we figured out the nuances of the gas water heater and possible problems indicating a breakdown of the radiator, let's talk about how you can repair it. But first, other malfunctions have to be ruled out.

Avoiding other column malfunctions

Most often, you can face a situation where the column does not initially ignite the flame. First, you need to determine what exactly led to this. After all, the problem may not be in the heat exchanger at all, but, for example, in dead batteries. Therefore, diagnostics are indispensable. Moreover, some of the breakdowns can be eliminated with your own hands, and in some cases it is necessary to cause gas service specialist.

External inspection of the water heater

Competent diagnostics will allow you to quickly carry out repairs on your own.

Self-repair of the column

It is not recommended to carry out self-repair if the gas water heater is under warranty. The service department can remove the device from warranty service

There are a number of elementary actions that should be performed before going to investigate the water heating device from the inside:

  1. Battery replacement and cleaning the power contacts.
  2. Checking the chimney draft and availability pressure in the cold water supply system.
  3. Fuse check (for speakers with turbocharged). You can turn the plug in the switch to change the position of the phase - important for imported models, since they are quite sensitive to this.
  4. Cleaning the strainer. It is a sump that can be found on a cold water pipe. Often, the mesh is a structural component of the water unit.
  5. Observe the ignition electrodes. To do this, it is enough to open a hot water tap, after which sparks should form. If the camera is closed, then you can listen to the body. Characteristic sounds should be heard, such as the clicking of charges.

The above steps may not always help. Then you have to look inside the column, for which you have to remove the case.

Cleaning the igniter

Each repair of the gas water heater should begin with checking the batteries and cleaning the contacts if they have oxidized. You also need to inspect and clean the igniter. There are models of columns that have a small window for access to the electrodes, which can be cleaned with a brush

Troubleshooting inside the column

If an external examination and replacement of the batteries did not help, then you can start troubleshooting directly inside the device.

To do this, it is necessary to remove the casing of the water heater and check the main components one by one. It is better to perform all actions with an assistant. He should be asked to open hot water, and he himself must monitor the movements of the stem. It is the responsibility of this element to act on the pressure plate to move it away from the button. microswitch.

In the case when the pusher does not perform any movements, then with a probability of 100% the problem lies in the water block. If this problem occurs, it is necessary to disassemble the unit in order to clean and change the membrane in it.

Also, the stem can press on the plate, but the button will remain pressed. In this case it is necessary to check the water regulator for limescale deposits. It should be found and cleaned.

If all of the above elements work in normal mode, the button is pressed out, but sparks are not formed, then in this situation the culprit may be himself microswitch. To make sure of this, you must disconnect its connectors and clamp the two terminals with a screwdriver. If in this case sparks begin to form immediately, then the switch is out of order and should be replaced.

Connector check

It is necessary to check by closing the connector that is connected to the impulse unit. Do not touch the microswitch plug.

Also, the solenoid valve may fail, due to which gas will not be supplied. To do this, check each of the sensors in the circuit by alternately closing. You can also use multimeter for dialing.

Heat exchanger repair procedure

If traces of leaks are found inside the structure, then the problem is much more serious. A leak can form from a copper radiator in a household gas water heater, which can be caused by deformation of the pipes. It can also appear due to irregularities in the operation of the water unit, which is characteristic of automatic gas water heaters. Such a violation indicates a malfunction of the gearbox, due to which the column may completely fail.

Hard water from the city water supply system, improper connection (grounding), frequent overheating of the column contribute to the formation of scale on the walls of the heat exchanger pipes. The material of the radiators is not particularly durable, therefore fistulas appear quite quickly on the surface of the pipeline and heat exchanger.

Owners of modern gas water heaters very often face such a problem. This is due to the fact that such devices use thin copper, often of low quality. To correct the problem, you can perform an ordinary soldering at the site of the fistula.

Stage # 1 - draining the water from the radiator

It should be noted that you cannot go straight to soldering. First you need to make sure that the column is disconnected from the gas and power supply.

It is also necessary to disconnect it from the water supply, completely empty the heat exchanger, which contains a sufficient amount of coolant. If this simple precaution is neglected, the incoming heat will constantly be removed due to the liquid.

Column heat exchanger

If a situation arises when the treated area of ​​the heat exchanger does not heat up to the required value, then it should be opened to drain the hot liquid.

All liquid from the heat exchanger cannot be removed with a tap. Therefore, you should unscrew the nut that is superimposed on the pipeline. Now it remains to get rid of the leftovers. For which you can use an ordinary vacuum cleaner or compressor, and you can also manually expel the air using a garden hose.

Stage # 2 - brazing copper pipes

When the heat exchanger has been completely drained, you can start brazing. But how to properly solder the heat exchanger in the gas column in the places of formation of fistulas? This is quite simple to do, since the whole process is well debugged. If you have never done this, we recommend that you read the instructions for brazing copper tubes.

To begin with, you should take an emery with fine grain and process the required area with it. Cleaning the fistula should be carried out until there are no oxides left. Determining their location is not difficult, since such copper has a greenish tint.

After completing the cleaning, rub the area with a cloth soaked in the cleaning agent. Now you can proceed directly to tinning. To do this, everyone individually selects solders for himself. You can also use the advice of professionals who recommend using POS-61. It remains to take a soldering iron from 0.1 kW of power and rosin as a flux.

In the absence of rosin, aspirin can be used. It is sold at the pharmacy. It will be effective in those situations when it is necessary to work with a problem area that cannot be cleaned out to the end.

Soldering point heating

In the case when the solder does not flow, but becomes loose, it is necessary to additionally warm up the point to be soldered. To do this, you can use a very weak soldering iron of 0.04 kW or a construction hair dryer.

When soldering is performed on the heat exchanger of the gas column in the required place, evenly distributing the layer of solder over the area, it is necessary to increase the thickness of the homogeneous mass to 2-3 mm. Thus, the fistula will close completely and will not appear again.

In addition to the main part of the heat exchanger, the entire piping must be inspected. Green oxidation can also occur on copper tubing. If this problem is not corrected, then in the future this will lead to the inevitable appearance of microcracks.

It should be noted that soldering is possible even if the smallest problem points and areas are found. It is immediately necessary to perform tinning and solder these places. If this is not done, then possible problems will arise every few months.

Soldering should be done even where it is impossible to reach. In this case, remove the radiator and disassemble it to get to the problem area.

Stage # 3 - search for defects after soldering

It is not always possible to detect all possible defects by visual inspection. Even sandpapering does not always give the desired result. In this case, special diagnostics performed under pressure can help.

To do this, apply a water jet inside the radiator unit. You can use a rubber shower hose that bends well. One side of the hose should be connected to the water supply channel. The second edge is with a radiator tube. It remains only to close one of the ends of the tube with a shut-off valve.

Crack in the column radiator tube

When searching for defects using tap water, a marker should be prepared. With its help, you should mark problem areas that are visually impossible to notice.

Now you need to start the tap that feeds the water heater. During this procedure, it is important to closely monitor the heat exchanger and all tubes. If there are barely noticeable cracks on the surface, they will immediately become visible. Water droplets will form at the places of their detection. The rest of the areas will be dry.

Thus, it will be possible to detect all problem areas requiring repair and solder them. At the same time, you can rinse the radiator, relieving it of scale.

If there is a lot of damage, or the pipe material is too thin and cannot be soldered, then it will not be possible to do without large financial investments. In such a situation, the purchase and installation of a new heat exchanger will have to be. And if the model you want is quite expensive, then you may have to think about choosing and buying a new speaker.

Conclusions and useful videos on the topic

In this video, you can clearly see how the heat exchanger is soldered:

A video on how you can repair the heat exchanger of a column with a digital display using soldering:

It is not necessary to resort to self-repair of the geyser if you are not confident in your own abilities. First of all, it is important to understand the principle of operation of the device and adhere to safety precautions. If you do not follow the rules, then you can endanger yourself and those close to you who live with you.

Do you have any questions about repairing a heat exchanger that we did not touch on in this material? Ask our experts in the comments section - we and other site visitors will try to help you.

If you want to share your successful experience of self-soldering a copper column radiator, tell us about this to our readers, add unique photos of the repair process - the feedback form is located below.

The boiler shocks through the water when turned on: what to do, causes, how to fix, ways

The boiler shocks through the water when turned on: what to do, causes, how to fix, waysWater Heaters And BoilersHeating

Boiler for hot water has recently become an indispensable type of household appliances. It is installed not only in summer cottages and in private homes. The unit can often be seen in city apartmen...

Read More
How to choose the right water heater: selection criteria, pros and cons

How to choose the right water heater: selection criteria, pros and consWater Heaters And BoilersHeating

The lack of centralized water supply or frequent accidents on heating mains make many urban and the vast majority of rural residents install autonomous supply complexes hot water. The main question...

Read More
Instagram story viewer