A home air recuperator is an integral part of ventilation and air conditioning systems. This device helps to create a comfortable indoor climate and significantly reduce heating costs. Before buying a recuperator, you should learn more about its purpose and principle of operation, pros and cons, selection rules and available varieties.
What is a recuperator
A recuperator for a home is a heat exchanger with a special design used for ventilation of premises. Its main task is to transfer thermal energy from the exhaust air flow to the supply air flow supplied to the interior of the room. Under such energy is meant both heat and refrigeration, therefore the exhaust flow is able to give heat and cold to the supply air at the same time, alternately warming it up or cooling it down. The recuperator is needed to pump stable energy from the air leaving the room. During its operation, the air flows do not mix, therefore the supply air is not contaminated with the extract air.
The device can generate good energy both in winter and summer. In winter, the recuperator must heat the supply air using the extract air. For this purpose, the cool air flow from the outside and the warm flow from the room are transferred to the inside of the heat exchanger, where the extract air heats up the supply air. This heating helps to save the power of an electric or water heater in ventilation systems. The presence of a recuperator also makes it possible not to lose most of the heat during ventilation and to reduce the heating load in winter.
If the supply air flow warms up to +10 degrees due to the exhaust air flow, the heating power in such a situation is calculated by 8 degrees, taking into account the heating. Since it corresponds to the temperature difference, the presence of a recuperator in this case would make it possible to save 82% of the system's capacity for ventilation.
Varieties and features of recuperators for a private house
A standard recuperator for a private house consists of a base with nozzles, built-in fans, heat exchange cassettes and filters. If it contains a single heat exchanger, the supply and extract air inside will exchange heat through the thin walls. In the presence of a double heat exchanger in the first, the exhaust flow gives energy to the intermediate carrier, in the second - the intermediate one transfers it to the supply. To choose the right option, you need to know on what principle each of the four types of devices works.
Lamellar
Lamellar devices are used in supply and exhaust systems of a monoblock type. These are devices based on a plate heat exchanger without moving parts, air moves through its channels during operation, the flows alternate with each other. The outlet and inlet streams are fenced with aluminum plates through which heating is carried out. Such devices are designed to maximize the area of contact with streams.Due to this, the efficiency of heat exchange and heat recovery in them is at a high level.
Rotary
Rotary devices are considered the most efficient in comparison with analogues. Their design is a wheel or rotor, the rotational axis of which corresponds to the movement of air along the lines. Half of such a wheel is located in the area of the exhaust flow, and the other half is in the area of the supply flow. The rotor itself consists of plates fastened to each other, through which air passes freely during operation. The rotary air recuperator first comes into contact with the exhaust flow that heats the wheel. After that, part of it enters the supply flow area, where it heats up and transfers the received heat. Then part of the wheel is again in the exhaust air zone, the cycle is closed.
During the transition of the wheel from the area of the exhaust flow to the supply part, a small amount of air enters the rotor. This causes mixing of streams, but this problem is practically absent in more expensive and modern devices.
Water
A conventional water air recuperator, suitable for a private house, operates on water used for heat transfer. The principle of its operation can be compared with the operation of a boiler replaced by a heat exchanger and built into the hood. The radiator in this device is a special element designed for the incoming flow from the outside. The water is heated in a heat exchanger and gives off heat in an additional element. Such recuperators are considered insufficiently energy efficient, but at the same time they are cheaper than powerful counterparts and operate according to a simple scheme.
For roof
Ventilation devices for roofs are used for the purpose of filtering, heating and supplying air to the inside of the object. The temperature of the air streams in them is regulated by a cooling element or a duct heater. The air flow passes partially or completely through the plates of the device. Such systems are installed on the roof ceilings using holes made in the roofs. This type of recuperator helps to take the recycled air collected from the ceiling and expels it into the atmosphere, transferring heat to the incoming stream. Air is blown into the ceiling or directed to the main area.
The roof device can also be part of a general ventilation scheme, in such situations it is indicated in the drawings. This device is easy to maintain and is available in several versions. They vary in power and are measured by the volume of air passing through them. The device is based on a frame-panel type construction made of aluminum profiles with a sheet thickness of up to 0.2 mm. The walls of its base are supplemented with mineral wool for insulation; such recuperators are also equipped with water, gas and electrical sections.
Advantages and disadvantages
Before installing the recuperation system, it is useful to familiarize yourself in advance with the pros and cons of such devices. The list of their advantages includes:
- the ability to completely replace the natural ventilation process;
- the device is cleaned with closed filters, this method protects the recuperator from contamination;
- the ability to reduce the cost of electricity, heating and additional systems by 30-50%;
- quick removal of excess moisture, foreign odors and harmful substances thanks to a constantly operating ventilation system.
Among the disadvantages of devices of this type, they note the presence of noise during operation, the need to clean the channels after long-term operation, periodic power failures, after which the system will not start automatically, as well as the costs at the initial stage of operation.
Recuperator selection rules
There are several important factors to consider when choosing a good recuperator. The local climate is taken into account, as this is of great importance for some types of appliances, for example, plate. For a home, it is advisable to choose the least energy-consuming model, therefore, when choosing, they pay attention to the power of the unit. Additionally, the area of the filtration material is taken into account, if it is large, the service life will significantly increase, while the cost of electricity will be reduced.
It is better to purchase devices with high-quality filters, the simplest ones are capable of removing only large particles of dirt, the more complex ones retain dust, including fine ones. The performance of the recuperator must be taken into account, which must correspond to the size and needs of the room. The intensity can also be influenced by the number or frequency of air flow changes. In terms of control, it is worth choosing devices with an automation system that provides more opportunities.
DIY installation and manufacturing
The installation of any recuperator is not difficult if it is carried out according to the rules. At the stage of installation and connection to the system, the device must be fixed on a solid surface and docked to one exhaust and supply channel. Further, the sections of the joints are treated with an airtight compound and the recuperator is placed in a heat-protective and noise-insulating housing. If the installation of the device is envisaged as part of a ventilation system project, this procedure should be entrusted to a specialist.
Duct recuperators require the laying of two air ducts in each room in order to supply and intake air flows. At the same time, the free cross-section of the gratings is calculated and the sockets are properly selected to eliminate unnecessary noise.
If necessary, the recuperator can be made by hand, the best choice in this case will be a plate-type system. It has a good real level of efficiency, a simple and reliable design, and does not require any connection to electricity.
Areas of application of the recuperator
Installing a recuperator in any home is necessary if its owners plan to create an optimal warm system with a fan, heating and air conditioning. The choice of a specific type of device depends on the needs, most often plate or rotary units are used.
Plate devices are easy to install and maintain, low cost and power, and they also have low efficiency. They are ineffective in heat exchange systems for large areas and are not suitable for rooms with high levels of humidity. It is advisable to use them to create ventilation systems in country houses, at IZhS facilities, in office or administrative premises, industrial areas and warehouses.
Rotary devices have good power, have a high level of efficiency, and do not depend on operating conditions. At the same time, they need high-quality service and regular technical inspection. Such devices are ideal for large workshops, large residential or administrative structures and buildings, rooms with high humidity and too dry air.
