The issue of energy efficiency concerns probably every property owner. Ordinary ventilation as a way to refresh the air in a room does not always work, in winter, these are quite large heat losses, and there is also a high probability of catching a cold, therefore, a heat exchanger was invented for ventilation – i.e. recuperator.
Simply put, the importance of the heat exchanger for ventilation is this, that the cold air entering from the street is heated by the exhaust air from the room, tj. the heat exchange of "dirty" air with fresh air takes place, without mixing air streams.
Well, It appears, that the introduction was understandable, so I will immediately proceed to the construction of the recuperator with my own hands. There are many examples of the manufacture of such devices on the network, which I actually used, adding some and reworking them for yourself. I needed such a heat exchanger for the rest room anyway, is a room of approx 24 m2, separated by a partition wall, for some time it served as the only living room.
For the production of the recuperator I needed:
- Chamber polycarbonate – 1 sheet 4mm (210 x 600 cm.)
- Extruded polystyrene foam (XPS)- 5 sheets 30 mm (120 X 60 cm)
- At the beginning Linear fans 100 mm (efficiency 100 litres/hour) — 2 pcs. – then converted to a larger one.
- Mounting foam.
- Plastic glue.
- Cables for connecting fans.
To begin with, I cut the polycarbonate sheets with a round knife, along a metal ruler.
One stream of air will pass directly through the polycarbonate honeycombs, a second, cutting through it, must be inserted between these plates, I cut strips for this (straws) from the same plates, then glue them together with plastic glue.
This is what it looks like after gluing the tiles.
In the photo after gluing the block, the arrows showed the movement of air flows. Streams run along the entire height of the block. There will be two such blocks.
The blocks are ready, must be the same height.
After the main heat exchanger blocks are made – recuperative, I made a box from extruded polystyrene XPS foam, I used mounting foam for gluing, I just put it on the ends and pressed it, I laid the heat exchange blocks for assembly, this is what it looks like.
I installed the fans, the other is not shown in the photo, yellow arrows show the gaps, which also need to be plugged with foam.
Actually, this homemade recuperator is almost ready, its assembly is next in line. As I wrote at the beginning of the article, it was made for a living room, but I installed it in the laundry room, from where fresh air is already supplied through the air ducts, through the heat exchanger and dirty humid air with unpleasant odors, is blown out. In the photo, arrows show, how air currents move.
The yellow arrows indicate the flow of exhaled air, and the blue arrows indicate the influent flow (fresh) air. As a result of the meeting of these flows, heat exchange takes place in the polycarbonate heat exchangers, which heats the incoming cold air to near room temperature, i.e. at outside temperature -5 do -10 degrees, if the temperature is lower, then of course the incoming air is colder.
The recuperator in its ready-assembled form looks like this.
The cover is fastened with long wood screws, glass can be embedded in it, to observe the condensate and other processes taking place in the heat exchanger, in my case, the cold air begins to heat up already in the air duct, so there is no condensate in the exchanger heater.
Troubleshooting or Conclusion.
To pump such air ducts, more efficient fans are needed, I had to add one more fan at the entrance to the air duct at the entrance to the wall, but it's better to mount the fans on 150 mm, with efficiency 300 liters per minute, only they are only in diameter 150 mm, you can buy a duct fan 125 mm, about good performance.
It is also convenient to set some kind of timer to turn on the household heat exchanger, to turn on once an hour 15 minutes or other time. You can use a simple timer.