Cleaning and maintaining the heat exchanger
Cleaning and maintenance of heat exchangers are essential tasks in maintaining their efficiency. Improper care or lack thereof can lead to damage to the heat exchanger. The most common problem is the formation of scale and deposits, which accumulate on the heat exchanger's surface. These impurities can cause reduced heat exchanger efficiency. Therefore, regular cleaning is necessary to ensure proper and efficient operation. Removing scale and deposits will help restore the full efficiency of the heat exchanger and ensure its long-term operation. If you're looking for answers to questions like whether every heat exchanger needs cleaning, how often it should be done, whether heat exchanger servicing can be done independently, and what it looks like in practice, read the article below.
Does Every Heat Exchanger Need Cleaning?
Regardless of whether we're dealing with a plate heat exchanger or a shell-and-tube one, servicing these devices is crucial to ensure their full functionality and extend their lifespan—though shell-and-tube heat exchangers generally have a lower tendency to accumulate deposits, so they may require less frequent cleaning.
Why Is Heat Exchanger Cleaning Necessary?
Deposits and contaminants that accumulate on the heat exchange surfaces of the exchanger during its operation reduce its efficiency, impeding fluid flow and, consequently, heat exchange, which can lead to the failure of the entire system to which it is connected. Therefore, regular heat exchanger cleaning is very important.
✅Heat exchanger cleaning should mainly involve internal cleaning to remove accumulated deposits and contaminants. For exchangers with a high accumulation of deposits, special chemical agents or cleaning techniques such as high-pressure water jet may be necessary. Regular heat exchanger cleaning helps maintain their efficiency and prolong their lifespan.
How Often Should we do Heat Exchanger cleaning?
The frequency of heat exchanger cleaning depends on the intensity of use and the operating conditions.
✅ It is recommended to clean it at least once every two years - this is the necessary minimum, but the more frequent recommendation is once a year for central heating systems - and at least once every one and a half years for domestic hot water systems. If the heat exchanger operates intensively or if a decrease in efficiency is observed, more frequent cleaning may be necessary than every 2 years - especially if the heat exchanger has been in operation in our system for several years. Regular cleaning helps maintain the heat exchanger in good condition and ensures its efficiency. Therefore, it's important to monitor the operation and efficiency of the heat exchanger and take appropriate cleaning actions as needed.
Can Heat Exchanger Cleaning Be Done by ourselves?
Yes, heat exchanger cleaning can be done by ourselves using the hydrodynamic washing method with water. Water with a descaler additive is an effective means of removing accumulated dirt, deposits, and contaminants from the heat exchanger. Thanks to high pressure, water reaches hard-to-reach places, ensuring effective cleaning. It's also advisable to leave the exchanger filled with descaler, for example overnight.
✅However, it's important to observe safety rules and use appropriate protective equipment during DIY cleaning. At the same time, it's worth noting that caution should be exercised when using pressure washers, which can force water at very high pressure - especially when cleaning a heavily used heat exchanger.
What Is Needed to Clean the Heat Exchanger?
To clean the heat exchanger, an appropriate cleaning agent is needed. A strong stream of water is effective in removing minor deposits and dirt. However, for more serious contamination, especially if the exchanger has been in operation for several years, chemical cleaning may be necessary. For this purpose, special agents are used that effectively dissolve hard-to-remove deposits from the heat exchanger. These are the same descaling agents used for cleaning central heating systems; as a last resort, household descalers used for kettles may suffice. Extreme caution and thorough rinsing of the plate exchanger after such cleaning are recommended, especially if the exchanger is used for domestic hot water and comes into contact with drinking water.
Chemical cleaning of larger plate heat exchanger units is a more advanced process that requires the use of specialized equipment and skills. Therefore, for larger models, you can always use the services of professional companies specializing in heat exchanger cleaning.
What Does Heat Exchanger Servicing Look Like - Step-by-Step Rinsing and Cleaning of the Exchanger
Heat exchanger servicing includes cleaning and rinsing the exchanger. The first step in cleaning a gasketed plate exchanger is to disassemble the plates (if we are talking about a dismantlable exchanger, not soldered), which are then cleaned with special chemical agents. Then the plates are reassembled. For a shell-and-tube exchanger, internal tube flushing is performed using water to remove accumulated dirt. Cleaning the exchanger depends on the type of contaminants and the type of exchanger. In the next part of the article, you can find out exactly how cleaning a plate exchanger looks depending on its type.
Cleaning a Plate Heat Exchanger
Not every plate heat exchanger can be cleaned in the same way. Cleaning plate heat exchangers varies depending on their construction - specifically, the method of plate connection. These devices come in 2 variants:
- Brazed exchangers (non-detachable connection) - in this case, it's not possible to dismantle the exchanger or remove individual plates without damaging the device. Therefore, the only way to clean soldered plate exchangers is chemical cleaning using agents that remove scale and contaminants from inside. Most often, this cleaning is done using a 5% solution of phosphoric or oxalic acid. The flushing direction should be opposite to normal exchanger operation.
- Screwed exchangers (detachable connection) - due to the possibility of disassembling the screwed plate exchanger, it's possible to remove individual plates and wash each of them with water containing descaler.