Ventilation systems with heat recovery: make a homemade recuperator

A ventilation unit with recovery is the most economical solution to date. But the purchase of equipment requires additional costs. We will tell you how to make ventilation with heat recovery with your own hands, spending very little money and time.

Heat Recovery Efficiency

recuperator operation principle
recuperator operation principle

Recovery is heat transfer, and in translation from Latin "return of the used". In the supply and exhaust ventilation, the recuperator takes heat from the air leaving the room and gives it to the cold supply. In winter, the difference between the temperature of the exhaust air and the air supplied to the house can reach 40 degrees. Usually, heating occurs due to heating appliances, that is, the wallet of the residents of the house.

In the heat, the recuperator is also useful, because the hot fresh air in the street makes the air conditioners work more intensively. Properly mounted do-it-yourself heat recuperator for ventilation will reduce by 4 - 5 times the difference between the temperature of the incoming and outgoing air flows.

Advantages of ventilation with heat recovery:

  • improvised heat recuperator in ventilation systems has an efficiency of at least 65%;
  • ventilation of the apartment with recovery allows you to save at least 30% of electricity bills;
  • a very simple design does not fail, since there are no moving parts in it;
  • the heat exchanger in the heat recuperator of the ventilation system is easy to maintain and maintain;
  • the device works without the use of electricity;
  • heat recovery provides not only ventilation of the apartment, but in some cases also regulates humidity.

The savings from heat transfer are higher, the greater the difference between the temperature in the house and on the street.

Do-it-yourself plate ventilation recuperator manufacturing

air flow pattern in the heat exchanger
air flow pattern in the heat exchanger

In a plate heat exchanger for ventilation, the flows of incoming and outgoing air are separated by plates of heat-conducting material.

Thus, the flows are not mixed, and heat is given off.

The ventilation system with a plate-type recuperator is simple and very common. Do-it-yourself ventilation with recovery can be done by a person with minimal skills of a mechanic.

Progress:

this is how the heat exchanger plates are placed
this is how the heat exchanger plates are placed

  • The basis of the recuperator for the ventilation system is a heat exchanger. The heat exchanger plates are cut out of thin sheet metal (galvanized) or textolite. It is necessary to cut plates of 20x30 cm. They must be very even and neatly cut. Metal is best cut with a jigsaw, avoiding the use of scissors for metal;

  • Between the plates a distance frame is made of technical cork, textolite or wood up to 3 mm thick. The frames are glued onto the plates with polyurethane adhesive. So that the resistance to air flow is not strong, the gaps between the plates should be about 4 mm .;
  • The structure is glued with a neutral sealant that does not cause corrosion;
  • The housing for the recuperator in ventilation is made of sheet metal or plastic, metal or MDF. Inside the box is lined with mineral wool or other insulation with a layer of 5 cm;
  • On the opposite sides of the box, two holes are made to which plastic flanges are attached, which are equal in diameter to the air pipes. All cracks are carefully sealed with silicone;
  • To drain condensate from a ventilation unit with heat recovery, it is necessary to equip a drain pipe.

Tips for manufacturing a plate heat exchanger for ventilation

  • recuperator operation scheme
    recuperator operation scheme

    To reduce the noise from ventilation with a heat recuperator, a duct is constructed from a moisture-resistant material (drywall), the walls of which are laid with insulating material;

  • When constructing ventilation with heat recovery with your own hands, it is necessary to take into account the speed of air movement, which can be increased by no more than 1 m \ s;
  • The total area of ​​the plates of the heat exchanger should be 3.5 - 4 square meters. meters to get the efficiency of the recuperator 60%;
  • It must be borne in mind that in frosts from -10 degrees and below the plate heat exchanger can be covered with ice. It is thawed from time to time, and a differential pressure sensor is installed in the warm half. When freezing the ventilation system with recuperation, the sensor will detect an increase in the differential pressure, air will be supplied through the bypass, and the heater will thaw due to the heat of the exhaust air.

Do-it-yourself tubular recuperator manufacturing

factory-made tubular heat exchanger
factory-made tubular heat exchanger

A ventilation unit with a tube-type coaxial recuperator is easier to assemble than a plate-type one. But it is more massive and the longer the device, the more efficient it is.

Materials for the manufacture of a tubular recuperator for ventilation:

  • PVC sewer pipe 200 cm long and 16 cm in diameter;
  • aluminum corrugated pipe 400 cm long and 10 cm in diameter;
  • couplers with a diameter of 10 cm.

Progress:

The corrugation is stretched and inserted in a spiral into a plastic pipe. Each end of the corrugation is attached to one of the rings of the splitter, processed by sealant.

On the one hand, the fan drives warm air from the room into the device, while cold air from the street penetrates between the walls of the plastic pipe and the corrugation. Through thin aluminum walls, heat is transferred from the exhaust air to fresh air.

The advantage of this system is that the supply and exhaust ventilation with heat recovery compared to plate ventilation in a smaller amount of condensate. And even its presence does not violate the action of the recuperator. At the same time, the tubular type recuperator is not suitable for installation in an apartment because of the size, but the design is very good for a private house.

Another type of ventilation system with heat recovery is presented in the video:

It is possible that the efficiency of the ventilation units we brought in with heat recovery is lower than that of factory-manufactured devices. But, by collecting any of them yourself, you save a lot of money, and subsequently you get effective installation and comfort in the room. Home-made ventilation systems with recovery are often equipped in garages and in country cottages.

Heating

Ventilation

Sewerage