A sharp drop in pressure in the heating system and constant overheating of the coolant often indicate that hydrodynamic flushing The internal channels have become a necessity. A heat exchanger washing device, also known as a booster or chemical cleaning circulation pump, allows for the efficient removal of lime deposits, rust and biological plaque without dismantling the boiler or complex equipment. Unlike mechanical cleaning, this method preserves the integrity of the tubes and restores the initial heat dissipation of the unit.
Use of specialized booster It allows you to drive aggressive acid or alkaline solutions through a closed circuit of the heat exchanger for several hours. This ensures deep penetration of the reagent in all the bends and hard-to-reach areas, where the bulk of the hardness salts usually accumulate. Well-chosen flushing-chemistry In combination with a circulation pump, it can extend the life of an expensive gas or electric boiler by several years.
The inner walls of the heat exchanger are eventually covered with a layer of scale that acts as a heat insulator, preventing the efficient transfer of energy from the burner to water. The thickness of the deposits of only 1 millimeter can increase fuel consumption by 10-15%, and also lead to local overheating of the metal and its subsequent burnout. The washing device creates forced circulation, allowing the solution to actively act on contaminants, softening and washing them out of the system.
The main element of the installation is powerful circulation-pump, which is fixed on the frame along with a container for a chemical solution. The device is designed to withstand the effects of acids, alkalis and corrosion inhibitors, so the tanks are often made of high-density polyethylene or stainless steel. When choosing equipment, it is important to pay attention to the pump performance and the material of the flow part, as they determine the durability of the device itself.
Principle of operation and design of the booster
The operation of the chemical washing plant is based on the creation of a closed circuit in which the liquid circulates under pressure, washing the internal surfaces of the heat exchanger. The solution in the tank is sucked by the pump and fed into the lower pipe of the heat exchanger, after which, passing through the channels, returns back to the container. This cycle is repeated many times, which allows you to use a relatively small amount of expensive reagent to clean the volumetric system.
The key node is circulation-pump, which must have sufficient power to overcome the hydraulic resistance of the overgrown scale heat exchanger. If the pump is too weak, the flow rate will not be sufficient to flush softened particles efficiently, and they may settle at the bottom of the system, creating new foci of blockages. Modern models are often equipped with speed regulators, which allows you to adapt the pressure for a specific task.
- 🛠️ Reagent capacity: It is made of chemically resistant materials, has a graduation volume and a drain valve for convenient disposal of waste liquid.
- ⚙️ Circulation pump: It provides pressure from 1 to 6 bar and a performance of 15 to 30 liters per minute depending on the model.
- 🔌 Connecting hoses: reinforced tubes with quick-removal fittings for connection to the pipes of the heat exchanger without using a tool.
⚠️ Attention: Never use a washing device with pumps that have aluminum or cast iron workwheels if you use acid solutions. Aluminum dissolves rapidly in acid, which will cause the pump to fail and contaminate the system with corrosion products.
Additionally, the design may include a pressure gauge to monitor the pressure in the circuit and a thermometer, since the scale neutralization reaction often takes place with the release of heat. Controlling temperature is important to prevent boiling of the solution, especially when using concentrated acids. Some professional models are equipped with automatic timers and pH sensors that signal the end of the reaction.
Technical nuances of the pump operation
When working with viscous solutions or with severe contamination of the system, the pump performance may fall. It is important to choose a device with a power reserve of about 20-30% of the calculated values to ensure stable circulation even in critical modes.
Types of heat exchanger washing devices
The market of climate engineering offers various modifications of installations, which are classified by type of drive, material of manufacture and purpose. The choice of a particular type depends on the frequency of use, the type of equipment being cleaned and the budget of the organization or private master. Understanding the differences helps avoid overpaying for unnecessary features or, conversely, buying weak equipment.
The most common electric boostersThese are operated from a standard 220B network. They are compact, easy to transport and do not require special skills to run. Electric models are ideal for service providers serving gas boilers in residential homes where there is no access to compressed air or industrial networks.
| Type of device | Power source | Advantages | Deficiencies |
|---|---|---|---|
| Electric booster | Network 220B | Autonomy, ease of use | Limited pump capacity |
| Pneumatic booster | Compressed air | High power, explosion safety | We need a compressor, noise at work. |
| Hand pump | Physical strength | Cheap, lack of electricity | Low efficiency, labour-intensive |
Pneumatic installations are driven by compressed air from the compressor. Inside the tank, excess pressure is created, which pushes the liquid into the heat exchanger. Such devices are often used in industrial facilities or in environments where the use of electricity is dangerous or impossible. They are highly reliable and there is no risk of short circuit when water enters.
For regular maintenance of household boilers, the best choice is a compact electric booster with a tank of 10-15 liters and a pump with a capacity of about 20 l / min.
Choosing a chemical reagent for cleaning
The effectiveness of washing depends on the correctly selected chemical composition. There is no universal means, since the composition of scale can vary depending on the hardness of the water and the operating conditions of the boiler. The main active substances are various acids, corrosion inhibitors and surfactants.
To remove carbonate deposits (the main component of scale), solutions based on hydrochloric, phosphoric or sulfamic acids are most often used. Sulfamic acid It is considered the safest for metals, as it is less aggressive to steel and copper, but it effectively dissolves calcium and magnesium salts. Phosphoric acid is good because it creates a protective film on the metal, preventing further corrosion.
- 🧪 Acid formulations: are designed to remove solid lime deposits, require neutralization after use.
- 🧼 Alkaline solutions: effective against organic pollution, oils and biological fouling in HVS systems.
- 🛡️ Corrosion inhibitors: special additives that protect the metal of the heat exchanger from acid corroding during washing.
⚠️ Attention: It is strictly forbidden to use hydrochloric acid of high concentration for washing heat exchangers made of stainless steel or containing aluminum elements. This can lead to end-to-end corrosion and irreversible damage to equipment.
An important step is neutralization acid residue after the washing cycle is completed. For this purpose, alkaline solutions are used, which bring the pH of the washing fluid to a neutral value before draining into the sewer. Ignoring this stage can cause acid residues to continue to break down the metal after the work is completed.
Technology of washing the heat exchanger without disassembly
The cleaning process begins with the preparation of the equipment and the connection of the booster to the heat exchanger. To do this, it is necessary to close the shut-off valve at the inlet and outlet of the boiler, drain the remaining water and dismantle the pipe sections, if the design does not allow connecting the hoses directly. Often special adapters or fittings corresponding to the diameter of the pipes are used.
After connecting the hoses from the booster to the pipes of the heat exchanger (feed and turn), the prepared solution is poured into the tank. The pump is turned on and the fluid begins to circulate. It is important to ensure that there are no air traffic jams in the system that can disrupt circulation and reduce cleaning efficiency. Air is removed through special valves or by short-term pressure increase.
☑️ Booster connection algorithm
The duration of the washing process depends on the degree of contamination and the type of reagent used. Usually, the cycle takes from 1 to 4 hours. In the process of work, it is recommended to periodically reverse the flow (change the direction of movement of the liquid), supplying the solution to one or another pipe. This helps to wash out the contamination from all corners of the heat exchanger.
After the chemical treatment, the system is washed with clean water to remove residues of the reagent and suspended dirt particles. Only after that the heat exchanger can be considered ready for installation and operation. Failure to comply with the technology can lead to the fact that the residues of chemistry provoke corrosion in the first days of operation of the boiler.
Diagnostics of results and prevention
To assess the quality of the washing can be in several ways. Visual examination (if possible to look inside) shows the absence of solid deposits. A more objective method is to control the parameters of the boiler after start-up: the temperature of the coolant at the output should quickly reach the specified values, and the temperature difference between the supply and the return should be stabilized.
If after washing the pressure in the system continues to jump or the pump noise does not disappear, it is possible that solid scale fragments remain in the heat exchanger or a repeat procedure with a stronger reagent is required. It's worth checking out. circulation-pump The boiler itself, as it could suffer from working in extreme conditions before cleaning.
- 📉 Noise reduction: The absence of humming and vibration during heating indicates an improvement in heat transfer.
- 🔥 Stable combustion: The burner works in a smooth flame without frequent switching on and off (beating).
- 💧 Normal pressure: Manometer indicators are stable under different modes of operation of the system.
⚠️ Attention: After washing, be sure to check all connections for leaks. Changes in pressure and temperature in the system could weaken old seals or reveal defects previously hidden by a layer of dirt.
To extend the intervals between washings, it is recommended to install magnetic filters or polyphosphate dispensers at the water inlet into the system. These devices prevent the formation of new scale and trap rust particles circulating in the pipes. Regular maintenance and use water-treatment They allow you to forget about the problem of overgrowth of the heat exchanger for a long time.
Carry out preventive washing of the system every 2-3 years, without waiting for the boiler to fail completely. It will be cheaper than replacing a heat exchanger or repairing a burnt boiler.
Frequently Asked Questions (FAQ)
How often should the heat exchanger be washed?
The frequency of washing depends on the hardness of the water and the intensity of the boiler use. On average, preventive cleaning is recommended every 2-3 years. If the water is very hard, the interval is reduced to 1 year. Signs of the need for washing are the rapid inclusion of the burner and a decrease in efficiency.
Can I use citric acid for washing?
Citric acid is a weak reagent and is only suitable for the removal of mild contaminants or prevention. For serious scale, it is ineffective, as it requires a long time and high temperature for the reaction, which is not always safe for boiler seals.
Is the washing dangerous for an old heat exchanger?
There is a risk that after removing the scale layer that covered the microcracks in the metal, leaks may appear. However, the operation of overgrown boilers is even more dangerous due to the risk of overheating and rupture. Before washing the old equipment, a visual inspection is desirable.
Do I need to neutralize the solution after washing?
Yes, neutralization is mandatory. The residues of acid in the system will continue to break down the metal even after the bulk has been drained. Neutralization is carried out with an alkaline solution until neutral pH is reached, which is confirmed by the indicator paper.