A special type of forced ventilation system is supply ventilation with heating and heat recirculation, which provides partial heating of the input air flow due to the warm air removed from the room using a special device - a recuperator. In this case, the main heating of the outside air is carried out by a conventional air heater.
Heat recovery in the supply air exhaust ventilation – this is not a new phenomenon, but it is still not widespread in our country. From a technical point of view, recovery is the most common heat exchange process. The word “recovery” itself is of Latin origin and means “return of what was spent.” Ventilation heat recuperators return some of the heat back into the room through heat exchange between the incoming and outgoing flows. The reverse process occurs in hot weather, when the outgoing cold air conditioning cools the oncoming warm air flow. In this case, it should be called cold recovery.
Why is recovery needed? Obviously, to save energy resources in the first place. A recuperator is a device in which heat exchanges between incoming and outgoing air masses. At normal 
ventilation, the temperature difference between incoming and outgoing air in the cold and hot seasons is significant. If, for example, it is -20°C outside and +24°C indoors, then the difference is more than 40°C. This difference will need to be covered by the heating system. In summer the difference is smaller, but it will also add load to the air conditioner. The recuperator allows you to reduce this difference to a minimum. Properly selected equipment ensures that at 0°C outside air and +20°C indoors, the difference between the incoming and outgoing flow is within 4°C, i.e. reduce it by five times. The efficiency of recovery decreases as the outside temperature decreases, but, nevertheless, the savings remain very noticeable. Moreover, when there is a significant difference between indoor and outdoor temperatures, recuperation is especially useful.
Many modern construction technologies require airtight and vapor-tight enclosing structures. For effective ventilation and removal of water vapor from rooms with sealed walls and double-glazed windows, forced supply and exhaust ventilation is required. Heat recovery in this case is the key to comfortable air exchange with minimal heat loss.
In the USA and Canada, long before the advent of recovery equipment, in order to ensure that not too much water enters the premises in winter cold air, and the summer is too warm, they came up with the idea of using a ground heat exchanger, which later became known as the “Canadian well”. His idea 
is that the outside air, before entering the premises, passes through supply air ducts buried in the ground, acquiring a temperature value close to +10°C - a constant soil temperature at a depth of 2 m or more. The Canadian well, in fact, is not a recuperator, but it reduces energy costs for heating and air conditioning. Ventilation of premises in traditional scheme with a Canadian well it is natural, but it can also be forced.
Recuperators as an element of ventilation equipment are actively used in European countries. The reason for their popularity is the economic benefits that heat recovery provides. There are two types of recuperators: plate and rotary. Rotary ones are more efficient, but also expensive. They are capable of returning 70-90% of heat. Plate ones are cheaper, but save less, in the range of 50-80%.
One of the factors influencing the efficiency of recovery is the type of room. If the temperature in it is maintained above 23°C, then the recuperator definitely pays for itself. And the more expensive the cost of energy, the shorter the payback period. The service life of recuperators is quite long, and with timely maintenance and replacement of inexpensive consumables, it is theoretically unlimited. Recuperators can be supplied as a monoblock or several separate modules.
The recuperator is a special type of heat exchanger to which the inputs and outputs of the supply and exhaust ducts of the ventilation system are connected. The polluted air removed from the room, passing through the recuperator, gives up its heat to the incoming outside air without directly mixing with it. This additional heating supply ventilation allows you to significantly reduce energy costs for heating the input air, especially in winter.
Plate recuperators
Plate recuperators are designed in such a way that the air flows in them do not mix, but contact each other through the walls of the heat exchange cassette. This cassette consists of many plates that separate cold air flows from warm ones. Most often, the plates are made of aluminum foil, which has excellent thermal conductivity properties. The plates can also be made of special plastic. These are more expensive than aluminum ones, but increase the efficiency of the equipment.
Plate heat exchangers have a significant drawback: as a result of the temperature difference, condensation forms on cold surfaces, which turns into ice. An ice-covered recuperator stops working effectively. To defrost it, the incoming flow is automatically bypassed by the heat exchanger and heated by a heater. Coming out warm air meanwhile melts the ice on the plates. In this mode, of course, there is no energy saving, and the defrosting period can take from 5 to 25 minutes per hour. To heat the incoming air during the defrosting phase, air heaters with a power of 1-5 kW are used.
Some plate heat exchangers use preheating of the incoming air to a temperature that prevents the formation of ice. This reduces the efficiency of the recuperator by approximately 20%.
Another solution to the icing problem is hygroscopic cellulose cassettes. This material absorbs moisture from the exhaust air flow and transfers it to the incoming air, thereby returning moisture back. Such recuperators are justified only in buildings where there is no problem of air humidification. The undoubted advantage of hygrocellulose recuperators is that they do not require electrical heating of the air, which means they are more economical. Recuperators with double plate heat exchangers have an efficiency of up to 90%. Ice does not form in them due to heat transfer through the intermediate zone.
Well-known manufacturers of plate recuperators:
- SCHRAG (Germany),
- MITSUBISHI (Japan),
- ELECTROLUX,
- SYSTEMAIR (Sweden),
- SHUFT (Denmark),
- REMAK, 2W (Czech Republic),
- MIDEA (China).
Rotary recuperators
Unlike lamellar ones, partial mixing of incoming and outgoing air occurs in them. Their main element– a rotor mounted in the housing, which is a cylinder filled with layers 
profiled metal (aluminum, steel). Heat transfer occurs during the rotation of the rotor, the blades of which are heated by the outgoing flow and transfer heat to the incoming flow, moving in a circle. The efficiency of heat transfer depends on the rotor speed, and it is adjustable.
In a rotary recuperator it is technically impossible to completely eliminate the mixing of incoming and outgoing air. In addition, this type of equipment requires more frequent and more extensive maintenance due to the presence of moving parts. Nevertheless, rotary models are quite popular due to their high heat recovery rates (up to 90%).
Manufacturers of rotary recuperators:
- DAIKIN (Japan),
- KLINGENBURG (Germany),
- SHUFT (Denmark),
- SYSTEMAIR (Sweden),
- REMAK (Czech Republic),
- GENERAL CLIMATE (Russia-UK).
WITH economic point In our opinion, heat recuperators will definitely pay off sooner or later, but much depends on how efficiently the recuperation itself will be organized. The equipment is highly reliable, and the consumer can count on a long period of operation. Many companies produce a wide range of air exchangers designed specifically for apartments. Thus, an air handling unit with heat recovery for a 2-3-room apartment can cost about 17,000 rubles. The performance of the ventilation system in apartments is in the range of 100-800 m³/h. For country cottages this figure is about 1000-2000 m³/h.
Recuperators with intermediate coolant 
This heat exchanger consists of two parts. One part is in the exhaust duct, the other in the supply duct. Water or a water-glycol solution circulates between them. The removed air heats the coolant, which, in turn, transfers heat to the supply air. In this recuperator there is no risk of transfer of contaminants from the exhaust air to the supply air. Changing the circulation rate of the coolant can regulate heat transfer. These recuperators have no moving parts, but they have low efficiency (45-60%). Mainly used for industrial facilities.
Chamber recuperators
The shutter divides the chamber into two parts by a shutter. One part is heated by the exhaust air, then the damper changes the direction of the air flow. Due to this, the supply air is heated by the warm walls of the chamber. Contamination and odors can be transferred from the exhaust air to the supply air. The damper is the only moving part of this heat exchanger. Its efficiency is quite high (70-80%).
Heat pipes
This recuperator consists of a sealed tube system. They're filled 
freon or other easily evaporating component. These substances evaporate when heated by the removed air. The vapor condenses in another part of the tube and again turns into a liquid state. In this heat exchanger, the transfer of contaminants is eliminated, there are no moving parts, and the efficiency is quite low (50-70%).
Many people believe that RECOVERY RECOVERERS are expensive, bulky, difficult to integrate into technological processes devices with a short service life, and their repair stops production for a long period, making the use of a recuperator ineffective. The listed disadvantages allow skeptics to put up with colossal losses of thermal energy and environmental problems. As a result, recuperators are not installed at all enterprises where this is advisable.
The solution may be the installation of Finned Plate Heat Exchangers (OPT™ type recuperators)
Technical features of OPT type recuperators
- due to the return of thermal energy, reduce the cost of its purchase by up to 40%;
- reduce fuel consumption by increasing the combustion temperature of exhaust gases (heating scheme for boiler rooms, furnaces, etc.);
- improve the quality characteristics of fuel combustion through the use of previously heated air, reduce mechanical underburning of fuel in the furnace heating cycle in boiler houses and other facilities;
- cool flue gases to comply with environmental requirements and sanitary standards;
- use the heat of exhaust gases for space heating, warming up the street air;
- For technological processes, requiring low temperatures, cool the exhaust flue gases;
- reduce flue gas temperatures, thereby reducing gas cleaning costs;
- replace those that require complex repairs recuperators are more reliable;
- successfully comply with the requirements of Law No. 261 Federal Law “On Energy Saving”;
Advantages of Finned Plate Heat Exchangers over traditional plate, rotor and shell-and-tube models
- possibility of use in aggressive and abrasive environments, in environments with heavy gas and dust contamination;
- increased operating temperature limits - up to 1250 C, while the service life of analog recuperators is reduced already at 800 C;
- optimized dimensions and weight - 4-8 times lighter than analog recuperators;
- significantly lower cost;
- shortened payback periods;
- low resistance values when air flows pass through the ducts;
- improved design that prevents the accumulation of slag;
- increased service life;
- extended working period before preventive measures;
- improved weight and size characteristics, facilitating installation and transportation of recuperators
Why can this type of recuperator be considered a smart choice?
- increasing the area of the heat transfer surface per unit volume and mass;
- high reliability of the recuperator used;
- significant reduction in the possibility of recuperator failure due to abrasive wear and thermal deformation;
- simplification of repair and maintenance processes for recuperators;
- possibility of modular design and assembly of recuperators
- The most common cases of using a recuperator.
Gas-gas heat exchangers are used in many areas, which can be divided into the following categories:
Processes with a low coolant temperature:
Interval from 20 to 60°C
- for small volumes of gases, for example, as a flue gas utilizer when operating gas boilers in a small room where the heat exchanger is used in the ventilation system.
- with large volumes of gases, for example, in the ventilation systems of workshops, concert halls, indoor stadiums and other large premises.
Interval 60 to 200°C
- for small volumes of gases, for example, to remove the smoke product of fuel combustion, which is released in the form of gas during many technological processes.
- for large volumes of gases, for example, the use of a gas heat exchanger is possible in the ventilation system of drying and painting shops.
Processes with an average level of coolant temperature.
The range is from 200 to 600°C, an example would be the recovery of heat from flue gases during the operation of boiler houses, and it is also possible to save coal by redirecting excess heat to warm up the air supplied to the furnace.
Processes that have high level coolant temperature.
- The range is from 600 to 800°C; for example, in the production of plastics, a heat exchanger may be useful for cooling the gas or for recovering heat carried by flue gases.
- The range is up to 1000°C and higher, which are observed in glass production, in metallurgy, oil and gas refining and other areas of production, where the heat exchanger will become the basis for solving problems such as saving coal, or will act as a utilizer of generated flue gases.
It is worth noting that the use of a gas-gas heat exchanger at an exhaust gas temperature of 45-50°C requires a separate efficiency calculation.
Conclusions
Installations with heat recovery can reduce energy costs for space heating by half. Their installation often pays for itself within the first heating season. Installing recuperators during construction and reconstruction allows us to partially reduce the load on the heating system of the entire building and eliminate a significant part of traditional heating equipment. The cost of installing recuperators is an investment not only in reducing heating costs, but also in ensuring optimal indoor climate conditions and, ultimately, in people's health.
Devices that can save heat and other types of energy are becoming increasingly important as energy prices are constantly rising. We have also long had no doubt about the need to breathe fresh, clean air indoors. The installation of popular plastic windows and sealed doors played a negative role in construction. They disrupt air exchange and lead to undesirable consequences. Against the backdrop of all these factors, ventilation systems with heat recovery come to our aid. They not only save us money, but also protect our health.
Rename the topic. Doesn't look like an educational program at all. He's only interested in PR.
Now I'll correct it a little.Advantages of a rotary recuperator:
1. High heat transfer efficiency
Yes, I agree. Most high efficiency among household ventilation systems.
2. Dehumidifies the air in the room, as it is not hygroscopic.
No one specifically uses a rotor for drying. Why is this included as a plus?Cons:
1. Large sizes.
I don't agree.
2. The rotor is a complex moving mechanism that is subject to wear, and operating costs will increase accordingly.
A small stepper motor that rotates the rotor costs 3 kopecks and rarely fails. You call it a “complex moving mechanism” that increases operating costs?
3. Air flows are in contact, due to which the admixture is up to 20%, according to some reports up to 30%.
Who said 30? Where did you get it? Please provide us with the link. I can still believe in 10 percent of the flow, but 30 is nonsense. Some plate recuperators are far from being hermetically sealed in this regard, and a small flow is normal there.
4. Condensate drainage is required
Dear educational programmer, read at least one instruction manual for the rotary installation for apartments and cottages. It is written there in black and white: at standard air humidity, condensate drainage is not required.
5. Fastening the PVU in one position.
Why is this a minus?
6. Dehumidifies the air in the room, as it is not hygroscopic.
If you know the ventilation system market, you have already paid attention to the development of rotors made of hygroscopic material. The question of how much this is necessary and how much all this hygroscopicity is needed, including in plate-type recuperators, is a rather controversial question and often not in favor of hygroscopicity.Thanks for the answer.
No one pretended to be an educational program. A topic for discussion and possible help for the user, as well as for me, as a user.“Since I am a slightly interested person, I will compare it with what I work with.” - I wrote at the very beginning. I compare it with what I'm working with.
The rotary type has larger dimensions than the plate type. Because I compare it with what I work with.
The fact that it has the highest efficiency indicators is, in my opinion, not true; the triple plate type has more efficiency and higher frost resistance. Again, I compare it with what I’m working with.
This is a moving mechanism and is subject to wear, so it costs three kopecks. This is good.
Mounting in one position is a minus. It is not always possible to install exactly as shown in the diagram.
Hygroscopy is needed to reduce operating temperature, at which the recuperator will not freeze.
During the ventilation process, not only exhaust air is recycled from the room, but also part of the thermal energy. In winter, this leads to higher energy bills.
Heat recovery in centralized and local ventilation systems will allow you to reduce unjustified costs without compromising air exchange. For thermal energy recovery, they are used different types heat exchangers - recuperators.
The article describes in detail the models of units, their design features, operating principles, advantages and disadvantages. The information presented will help in choosing the optimal option for arranging the ventilation system.
Translated from Latin, recuperation means compensation or return. With regard to heat exchange reactions, recovery is characterized as a partial return of energy expended on a technological action for the purpose of application in the same process.
Local recuperators are equipped with a fan and a plate heat exchanger. The inlet “sleeve” is insulated with noise-absorbing material. The control unit of compact ventilation units is located on the internal wall
Features of decentralized ventilation systems with recovery:
- Efficiency – 60-96%;
- low productivity– the devices are designed to provide air exchange in rooms up to 20-35 sq.m;
- affordable price and a wide selection of units, ranging from conventional wall valves to automated models with a multi-stage filtration system and the ability to adjust humidity;
- ease of installation– for commissioning, no installation of air ducts is required; you can do it yourself.
Important criteria for choosing a wall inlet: permissible wall thickness, performance, efficiency of the recuperator, diameter of the air channel and temperature of the pumped medium
Conclusions and useful video on the topic
Job comparison natural ventilation and forced system with recovery:
The principle of operation of a centralized recuperator, calculation of efficiency:
The design and operating procedure of a decentralized heat exchanger using the Prana wall valve as an example:
About 25-35% of the heat leaves the room through the ventilation system. Recuperators are used to reduce losses and effectively recover heat. Climatic equipment allows you to use the energy of waste masses to heat the incoming air.
Do you have anything to add, or do you have questions about the operation of different ventilation recuperators? Please leave comments on the publication and share your experience in operating such installations. The contact form is located in the lower block.
Any enclosed space needs daily ventilation, but sometimes this is not enough to create a comfortable and pleasant microclimate. In the cold season, when the windows are open for ventilation, heat quickly escapes, and this leads to unnecessary costs for heating. In the summer, many people use air conditioning, but along with the cooled air, hot air from the street also penetrates.
To balance the temperature and make the air fresher, a device called an air recuperator was invented. IN winter time it allows you not to lose room heat, and in the summer heat it prevents hot air from entering the room.
What is a recuperator?
Translated from Latin, the word recuperator means - return receipt or return, regarding air, we mean the return of thermal energy that is carried away with the air through the ventilation system. A device such as an air recuperator copes with the task of ventilation, balancing two air flows.
The principle of operation of the device is very simple; due to the temperature difference, heat exchange occurs, due to which the air temperature is equalized. The recuperator has a heat exchanger with two chambers; they pass exhaust and supply air flows through themselves. The accumulated condensate that forms due to the temperature difference is automatically removed from the recuperator.
The recovery system not only allows you to ventilate the air in the room, it significantly saves heating costs, since it effectively reduces heat loss. The recuperator is capable save more than 2/3 heat leaving the room, which means that the device reuses thermal energy in one technological cycle.
Device classification
Recuperators differ in their coolant flow patterns and design, as well as in their purpose. Are there several types of recuperators?
- Lamellar
- Rotary
- Water
- Devices that can be placed on the roof.
Plate recuperators
They are considered the most common because their price is low, but they are quite effective. The heat exchanger located inside the device consists of one or more copper or aluminum plates, plastic, very strong cellulose, they are in a stationary state. Air entering the device passes through a series of cassettes and does not mix; during operation, a simultaneous cooling and heating process occurs.
The device is very compact and reliable, it practically does not fail. Plate-type recuperators operate without consuming electricity, which is an important advantage. Among the disadvantages of the device is that the plate model cannot work in frosty weather; moisture exchange is impossible due to freezing of the exhaust device. Its exhaust ducts collect condensate, which freezes at sub-zero temperatures.
Rotary recuperators
Such a device is powered by electricity; its blades are powered by one or two rotors. must rotate during operation, after which air movement occurs. Usually they have a cylindrical shape with plates tightly installed and a drum inside. They are forced to rotate by air flows, first coming out room air, and then, changing direction, the air comes back from the street.
It should be noted that rotary devices are larger, but Their efficiency is much higher than lamellar ones. They are great for large rooms - halls, shopping centers, hospitals, restaurants, so it is not advisable to buy them for home. Among the disadvantages, it is worth noting the expensive maintenance of such devices, since they consume a lot of electricity, they are not easy to install due to their bulk, and they are expensive. A ventilation chamber is required for installation due to large sizes rotary recuperator.
Water recuperator located on the roof
Recirculation devices transfer thermal energy to the supply heat exchanger using several coolants - water, antifreeze, etc. This device is very similar in performance to plate recuperators, but differs in that it is very similar water system heating. The disadvantage is low efficiency and frequent maintenance.
A recuperator that can be placed on the roof saves space in the room. Its efficiency is a maximum of 68%, it does not require operating costs, all these qualities can be attributed to the advantages of this type. The downside is that such a recuperator is difficult to install; it requires special system fastenings Most often this type is used for industrial facilities.
Natural ventilation must be designed and installed in any residential building, but it is always influenced by weather conditions, depending on the time of year, the strength of ventilation depends on this. If the ventilation system works effectively in the frost in winter, then in the summer it practically does not function.
Tightness of a residential building can be reduced by improving natural ventilation, but it will give noticeable results only in the cold season. There is also negative side, for example, heat will leave a residential building, and incoming cold air will require additional heating.
To prevent this ventilation process from being too costly for home owners, it is necessary to use the heat of the air removed from the room. It is necessary to make forced air circulation. To do this, a network of supply and exhaust air ducts is laid out, then fans are installed. They will supply air to separate rooms and this process will not be associated with weather conditions. Especially for this purpose, a heat exchanger is installed at the intersection of fresh and contaminated air masses.
What does an air recuperator provide?
The recovery system allows you to minimize the percentage of mixing of incoming and exhaust air. The separators that are in the device carry out this process. Due to the transfer of flow energy to the boundary, heat exchange occurs; the jets will pass parallel or crosswise. The recovery system has many positive characteristics.
- A special type of grille at the inlet of air flows retains dust, insects, pollen and even bacteria from the street.
- Purified air enters the room.
- Polluted air, which may contain harmful components, leaves the room.
- In addition to circulation, the supply jets are cleaned and insulated.
- Promotes sounder and healthier sleep.
The positive properties of the system make it possible to use it in various types of premises to create more comfortable temperature conditions. Very often they are used in industrial premises where ventilation of a large space is necessary. In such places it is necessary to maintain a constant air temperature; this task is handled by rotary heat exchangers that can operate at temperatures up to +650 o C.
Conclusion
The necessary balance of fresh and clean air with normal humidity can be provided by a supply and exhaust ventilation system. By installing a recuperator, you can solve many problems also related to saving energy resources.
When choosing an air recuperator for your home, you need to take into account the area of the living space, the degree of humidity in it and the purpose of the device. You should definitely pay attention to the cost of the device and the possibility of installation, its efficiency, on which the quality of ventilation of the entire house will depend.
Heat recovery has become quite often used recently in ventilation systems. If we consider the process itself in more detail, we must first decide and understand what the term recovery itself means. Heat recovery in ventilation systems means that the air being passed through, which is removed by special installations, is passed through a filter system and supplied back.
Worth paying special attention that in ventilation systems With some of the exhaust air, some of the heat is drawn out of the room. And this is exactly this one thermal energy and comes back.
These systems are effectively used in large industries and large workshops, since in order to ensure the optimal temperature for such premises in winter it is necessary to incur large expenses. These installations can significantly compensate for such losses and reduce costs.
Even in a private home, ventilation units with heat recovery will be quite relevant today. Even in an individual house, ventilation is always carried out and when air circulates, heat also leaves any room. Agree that it is simply impossible to seal the building completely and thereby avoid any heat loss.
Today, these systems should be used even in a private home for the following reasons:
- For quick removal air with a large admixture of carbon dioxide;
- For influx required quantity fresh air to residential premises;
- To eliminate high humidity in rooms, as well as eliminating unpleasant odors;
- To save heat;
- And also to remove dust and harmful microorganisms that may be contained in it.
Supply air systems with recovery
An air handling unit with heat recovery is beginning to be in increasing demand among private homeowners. And its advantages, especially in the cold season, are very high.
As you know, there are many ways to provide a living space with the necessary ventilation. This and natural circulation air, which is mainly carried out by ventilation of rooms. But you must admit that it is simply impossible to use this method in winter, since all the heat will quickly leave the living quarters.
If in a house in which air circulation is carried out only naturally there is no more effective system, it turns out that in cold weather the rooms do not receive the required volume of fresh air and oxygen, which subsequently negatively affects the well-being of all family members.
Of course, recently, when almost all owners install plastic windows and doors, it turns out that arranging ventilation in a natural way is simply ineffective. Therefore, there is a need to install additional equipment that can ensure good air circulation indoors. And, of course, every owner will agree that they would like any system to use energy sparingly.
And right here is the most the best option There will be heat recovery in ventilation systems. IN ideal It is advisable to purchase a unit that could also provide humidity recovery.
What is moisture recovery?
Any room should always maintain a certain level of humidity at which each person feels most comfortable. This norm ranges from 45 to 65%. In winter, most people experience excessively dry indoor air. Especially in apartments, when the heating is turned on full and the air becomes very dry with a humidity of about 25%.
In addition, it often turns out that not only humans suffer from such changes in humidity. But also floors with furniture, as we know, wood has high hygroscopicity. Very often, furniture and floors dry out from too dry air, and in the future it turns out that the floors begin to creak and the furniture begins to fall apart. These installations will primarily maintain the required level of humidity in any room, regardless of the time of year.
Types of recuperators
In individual residential buildings Ventilation systems with centralized heat exchangers are most often installed. In addition, today you can choose from several types of recuperative ventilation designs, but the following are in higher demand:
- Lamellar.
- Rotary.
- Chamber.
- Having an intermediate coolant.
Plate type heat exchangers
The most simple designs for ventilation systems. The heat exchanger is made in the form of a chamber divided into separate channels located parallel to each other. Between them there is a thin plate partition, which has high thermal conductivity properties.
The principle of operation is based on the exchange of heat from air flows, that is, exhaust air, which is removed from the room and gives up its heat to the supply air, which enters the house already warm, thanks to this exchange.
The advantages of this technology include:
- easy device setup;
- complete absence of any moving parts;
- high efficiency.
Well, one of the most significant drawbacks in the operation of such a recuperator is the formation of condensation on the plate itself. Typically, such heat exchangers require additional installation of special drop eliminators. This is a necessary parameter, since in winter the condensate can freeze and stop the device. That is why some devices of this type have built-in defrosting systems.
Rotary heat exchangers
Here main detail takes over the rotor, which is located between the air ducts and heats the air through constant rotation. Ventilation with heat recovery rotor type has very high operating efficiency. This system allows you to return about 80% of the heat back into the room.
But a significant drawback is the inferior performance of the system regarding dirt, dust and odors. There are no densities in the design between the rotor and the housing. Because of them, air flows can mix and therefore all contaminants can come back again. And naturally, the noise level here is an order of magnitude higher than that of a plate heat exchanger.
Chamber type heat exchangers
In this type of recuperator, the air flows are separated directly by the chamber itself. Heat exchange occurs thanks to a damper that periodically changes the direction of air flow. This system has high operational efficiency. The only disadvantage is the presence of moving parts inside the device.
Heat exchangers with intermediate media
The operating principle of this device is almost similar to that of plate recuperator. Here the heat exchanger is a closed loop of a tube. There is a constant circulation of water or a water-glycol solution in it. The efficiency of heat exchange processes directly depends on the circulation rate in a closed fluid circuit.
In such a device, mixing of air flows is completely eliminated. The only downside is the lack of efficiency. Such a device is capable of returning approximately 50% of the heat taken from the room.
Heat pipes
It is worth highlighting one more type of recuperator. Heat recovery in a home using heat pipes is quite effective. Such devices are sealed tubes made of metal that has high heat-conducting properties. Inside such a tube there is a liquid that has a very low temperature boiling (usually freon is used here).
Such a heat exchanger is always installed in a vertical position, with one of its ends located in the exhaust duct and the other in the supply duct.
The principle of operation is simple. The drawn out warm air, washing the pipe, transfers heat to the freon, which, boiling, moves upward with a large amount of heat. And the supply air washing the top of the tube takes this heat with it.
The advantages include high efficiency, quiet operation and high efficiency. So today you can save a lot on heating your home, paying some of it back.