Even residents of apartment buildings equipped with a centralized hot water supply system face the problem of lack of hot water.
If the owners of private houses did not take care of installing a double-circuit boiler that provides the cottage with both heat and hot water, then they also begin to look for a way to get enough heated water for household needs.
Advantages and disadvantages
Even in the ideal case, when the house is gasified, installing a geyser does not always completely solve the problem of obtaining hot water in sufficient quantities.
It takes some time for hot water to appear in the tap, and when using the shower, the water temperature can drop sharply if you start using the water tap in the kitchen. These shortcomings are always inherent in instantaneous water heaters, where water is heated using gas or electricity.
When using an indirect heating boiler, such problems do not appear, since they the device allows you to keep the temperature of the water constant.
If we calculate the cost of obtaining hot water when using instantaneous water heaters and compare it with the cost of heating water with indirect heating boilers, it is obvious that the work of the latter is much cheaper for consumers.
However the purchase of such an industrial water heater will cost a considerable amount. Usually the required volume of construction is calculated based on the number of people living in the house. At least 50 liters of hot water are required per day for one person.
For a family of four, it is necessary to purchase an indirect heating boiler with a minimum volume of 200 liters. Depending on the manufacturer, the purchase of such a model will cost the owners of the house 35–450 $.
Since its design is not too complicated, many homeowners make the device themselves.
The principle of operation of an indirect heating boiler
Before undertaking the manufacture of such a heating device, you should understand how it works, and for this, study its device. An indirect heating boiler is a conventional tank with pipes inside. A coolant circulates through them.
The heating system can be the source of heat. Water is supplied inside the tank, gradually heating up to a temperature determined by the parameters of the coolant. Since water is taken for household needs from the top of the tank, its temperature remains stable, it is convenient to use heated water.
Thus, it is possible to provide a private house, where there is a heating system that operates on any type of fuel, with hot water in sufficient quantities. An indirect heating boiler can also be used in multi-storey buildings by connecting it to the heating system.
True, it will function only during the heating season. In order for the device to be used in the absence of heating, an electric heating element is added to the design, including it in the network as needed.
Types of homemade indirect heating boilers
In the most popular design option, a coil made of a metal pipe is used to pass the coolant. The coil is placed in a tank, the tank is filled with water, and then the coolant is passed through.
Upon contact with the coil, cold water in the tank heats up. If the pipes with the coolant are placed along the walls of the tank, the storage boiler will not work worse.
Home craftsmen are constantly coming up with new device designs. There is an option that allows you to do without pipes for the coolant. In this case, two containers with different diameters are used. They are inserted into each other, cold water is supplied to the smaller one, and the coolant is given a place between their walls.
However the use of a coil gives faster heating of water, since a pipe of this shape is longer, and this makes it possible to use the coolant more efficiently. There are other designs, but the above are the easiest to make yourself.
Materials and parts required for the manufacture of a boiler
First of all, you need to choose a container for the manufacture of the tank. The best material choice is stainless steel. You can use a ready-made barrel, order a tank of the required size, or purchase a gas cylinder. It has sufficient strength, suitable dimensions and shape. Another option for making a tank can be a container made of heat-resistant plastic.
Holes of the required size should be made in the tank. Two holes will be needed to connect the cold and hot water supply pipes. One of them is made at the bottom of the tank, and the other at the top. Two more holes will be needed for mounting the coil, designed for the passage of the coolant.
For coil manufacturing a brass or copper tube is perfect. These materials transfer heat well, and they are quite easily given the necessary shape. You can also use small diameter plastic pipes.
In order to make a coil, a pipe of the required length is wound on a base, which can be a strong metal pipe or a rounded log.
In order for the tube intended for the coil to be bent evenly, without creases, it is completely filled with sand before starting work. Then the coil will turn out to be of the correct shape, of the same diameter along its entire length.
Based on the volume of the tank, the temperature of the coolant and the temperature of the incoming water, the required length of the coil is calculated. To do this, use a special calculation formula. For a tank with a volume of 200 liters, when using a coil with a diameter of 10 mm, its length will be about 15 meters.
Even before the installation of the storage boiler, it is necessary to decide how its thermal insulation will be carried out. It will not be possible to do without it, since natural heat losses are large and the efficiency of the water heater will be too low. The ideal way to insulate the tank would be to place it inside a suitable container, and then fill it with polyurethane foam.
To assemble the boiler, you should take care of the presence of fittings, nuts, rubber seals, ball valves. When manufacturing a structure from a gas cylinder, welding equipment will be required.
Watch a video on how to make an indirect heating boiler with your own hands:
Installation of an indirect heating boiler, in which the coolant is supplied through the coil, begins with its installation. A thread is cut at the ends of the coil, onto which a lock nut is screwed, and then they are inserted into the prepared holes in the tank so that the lock nuts have a stop.
The threaded portion of the coil must extend beyond the surface of the tank. Rubber gaskets are put on them, and threaded couplings are screwed on top of them. As a result of these manipulations, the coil is securely fixed, while it becomes possible to connect it to the heating system.
The next stage of work is to connect the tank to cold water and drain the hot water tap to the required place. The final part of the installation will be the insulation of the water heater, but before that you should check the tightness of all connections.
Thus, you can provide your home with enough hot water at minimal cost. The cost of purchased materials will cost a small amount, especially when compared with models made in an industrial way. The price of a factory-made boiler starts from 200 $ for Drazice OKC models.
Video on how to properly connect an indirect heating boiler with your own hands: