Installation of indirect heating boiler in the attic

Step by step diagram of how to connect an indirect water boiler to the water supply and electricity with your own hands

Centralized hot water supply. a myth rather than reality. In most settlements this good of civilization ceased to be available many years ago. But there is a great alternative. water heaters, aka boilers. Many models of such units are available for sale: flow-through, storage, electric, gas, etc.д.

And if the connection of gas water heaters should deal with specially trained people, the electric boiler can be connected to the water supply by your own efforts. The presented guide will help you thoroughly understand all the intricacies and nuances of this activity.

The principle of recirculation

Many such boilers are equipped with a special tap to connect the water recirculation lines for DHW to ensure a constant temperature of hot water. Therefore, when installing the system lay an additional pipe, which ensures the movement of the medium in a closed loop with the possibility of withdrawal. DHW recirculation system makes sense if the length of the pipes will be more than 10 m. Its principle is quite simple, with minor design differences, depending on the scheme of piping of the indirect heating boiler, the way of wiring for specific consumers: collector, two-pipe or standard.

In a manifold scheme, the water passes through the manifolds in series, and returns to the starting point of the system with an indirect heated water heater. In the two-pipe. water moves in parallel with the cold water, but at the end consumer, it does not stop, and returns to the starting point.

In the standard scheme, a return line is used for the trimmer, from the farthest water intake having a common point at the outlet valve of the indirect heating boiler to the T-piece or to the cold line in the tank. Therefore, hot water circulates and arrives with the calculated parameters to the consumer.

Pump recirculating hot water is installed in the return. Adjustment of the system is performed by a temperature sensor and timer that turns on the equipment of the system, usually during peak demand for hot water.

Indirect heating. used when the user in the heating scheme is a secondary energy, for example, in an autonomous heating system powered by a boiler, in which part of the energy goes to heating, and another. to BKNR.

The heating medium moves along the internal coil of the vessel, heating the water of the external heating circuit. After which the cold coolant pump is sent to the boiler for re-circulation, and the water from the storage tank enters the DHW system.

Structurally, the connection of boilers can be performed with multiple circuits, in the form of coils, working from different heat sources: the boiler coolant, flue gases, a solar generator and an electric heating element.

Connecting several boilers in one system

In regions where there is an unstable gas or electricity supply resort to the installation of two boilers, such as solid fuel and gas. Two units can operate under different schemes:

  • Connection in series. a thermal accumulator is installed between the units, which receives heated coolant from the solid fuel boiler. Then it is sent to the system with a gas device, and after that is distributed to consumers.
  • Parallel connection. in this case the work of solid fuel boiler is controlled by the safety sensors. A three-way valve is also installed, which can be used to shut down any of the units.

Multi-circuit heating systems are equipped with hydraulic distributors that compensate the pressure difference and balance the flow of the heat carrier. Sometimes you can organize the system without hydraulics, then the pressure is regulated by balancing valves.

Which heating units can be connected to

Suitable indirect water heater for a solid fuel boiler and the water stays hot for a long time. Combines well with gas, electric or oil-fired heating appliances. No restrictions on the type of fuel. That is, installation of a boiler of indirect heating is carried out in conjunction with any boiler that has an output on the water circuit. Combined type will solve the problem when the heating of the main heat exchanger will be turned off.

Installation depends on what model is chosen: with an autonomous system to regulate water heating or not. Autonomous control system is much more convenient. In the second case we will have to think about a temperature control system. Connecting an indirect water heater to a single boiler. responsible process, which must be prepared for. In any case, if the house is a single boiler, the boiler is considered the best solution for DHW.

Advice. If the boilers are large in volume, it makes sense to install several heat exchangers to reduce the time of water heating. For the same purpose, as well as for water to hold the temperature for a long time, boilers are made with insulation.

Connecting the boiler to the water supply of different materials

The boiler is bundled in the heating system using both traditional steel pipes and more modern polypropylene and metal-plastic pipes. A cheaper option. polypropylene.

The choice will depend on the price of the project and the operating temperature of the heating medium at the boiler outlet. For example, the temperature of the coolant in a solid fuel boiler is poorly adjustable, there may be cases where it will spontaneously grow to 100 C, so in this case it is better to install steel pipes.

Although they are less durable, but designed for high temperature operation of solid fuel devices.

installation, indirect, heating, boiler

Polypropylene piping

Polypropylene pipes are easy to install using a specialized soldering iron and scissors for cutting pipes. After selecting the place of inclusion in the pipeline cut out a section of width equal to tee, minus 20 mm: 10 mm for each.

With a soldering iron, heat the pipe and fitting to the required technical condition and connect them. At the same time it is forbidden to twist them, because such would be able to break the tightness of the connection.

Next, by connecting parts of pipes of different lengths and corners, the supply to the pipe nipples of BKN is performed. A socket with thread is soldered on the end of the pipe section, and then the entire line for the trimmer is firmly connected.

Tapping into a metal pipe

Today you can connect BKN to water supply networks without welding, for this purpose there is a modern transitional device “vampire”, which has a technological hole and a clamp in the body. Installation of such a construction is very simple. Choose a point of tie-in, wiper the area.

On top of the prepared area is installed clamp with a heat-resistant gasket and tightened with bolts to secure it. Then close the water supply and drain it from the desired section of the pipeline by opening the tap on the faucet hot water.

Next, through a hole in the clamp drill pipe section with an electric drill and then screw the valve and continue piping BKN according to the scheme.

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This is the most reliable and simple strapping method of boiler BKN to two-circuit boiler. Metal plastic is simply bent at the desired angle of withdrawal, and connections of the units are made with various crimp fittings.

Before strapping the pipe to the tap, the desired length and size of pipe is cut. Next, choose the point of cutting, taking into account the size of a tee and the part of the pipe that will be occupied by the connection.

installation, indirect, heating, boiler

Special scissors are used to prepare the hole in a small area. Remove the nuts from the tee, and together with the fixing rings put on the different ends of the pipe. Flare the ends of the metal plastic using a special calibrator or screwdriver.

The tee is inserted as far as the stop, then slide the rings and use a wrench to tighten the nuts. You can also use fittings for metal plastic pipes, which require pressurization and additional specialized tools and devices.

The principle of operation of the indirect heating boiler

This option is ideal for an apartment building, but it can be used without extra costs only during the heating season. For the period when the central heating is off, it can be equipped with an electric heating element. In this case, you will have to pay more for electricity, but the heating can be turned on as needed.

Principle scheme of operation of the water heater of indirect heating

The same system can be arranged in a detached house, if it has an autonomous heating from the boiler.

Construction and materials

This type of boiler consists of a container. Which can have any volume. It is best made of stainless material, so it will last a longer time, and heated water will always be clean. For the capacity of the boiler is usually used barrel, a new gas cylinder or make a tank to order.

  • In the middle of the tank is set pipe, twisted in the form of a coil, it and will circulate coolant. As a pipe it is good to use copper or brass. metals with good heat dissipation. However, as an option, it is possible to choose for this purpose and metal-plastic pipe of small diameter.
  • To make a neat coil, a long tube (about 15 meters) is wound onto another pipe of larger diameter, a wooden flat log or other suitable cylindrical object.
  • The number of turns on the coil depends on the shape and height of the vessel. but the longer the tube twisted in the coil, the faster you can get heated water.
  • The pipe ends are led out of the tank in different places. On top of the tank is a branch pipe, which will receive the coolant from the heating system. After passing through the coil, it will return to the heating circuit through another pipe located in the bottom of the tank.
  • Two holes are provided in the tank: for filling it with cold water and for receipt of heated water. The first is arranged at the bottom of the tank, and the second at the top, from where the hot water is distributed to the desired points: a shower or a kitchen faucet.
installation, indirect, heating, boiler

Diagram-drawing of indirect water heater connection

In the diagrams you can clearly see the connection and circulation of water and coolant heating system.

Another option could be a boiler of the same type, but without a coil. For it we need two tanks. large and compact size. Small tank is installed in the middle of the large tank, it will perform the role of the heat exchanger. The coolant will not circulate through pipes. it passes through an internal compact vessel. The principles of operation and conduct of pipes for the circulation of heated water is identical to the first option.

It should be said that the principle of the device of such a device is quite simple, so. Based on this, you can invent your own design of water heater of indirect type.

If you want you can equip the boiler with a heating element

In these variants of the boiler it is also possible to use an electric heating element. which is built into the tank from below. Therefore it is better if the boiler will be hung on the wall with brackets. You can also install the body on high legs, which are easy to make from an angle or fittings. Heating element, in fact, is the same boiling pot, but you need to choose its capacity. it will depend on the volume of the boiler.This heating element can be purchased in a specialized store.

Scheme of the indirect heating boiler with a heating element

How to install a boiler with your own hands

When independently installing the water heater will need to follow strict safety regulations, because the device has dangerous factors for humans. the voltage of 220 V and hot water with a temperature of up to 80 C. Therefore it is necessary to turn off all the taps and turn off the electrical supply before performing the installation work.

Modern designs of water heaters do not involve direct inclusion in the network. they work from an ordinary household socket, but first requires checking its capacity, so she with a reserve could provide the work of an electric water heater.

In order to decide whether to do its own installation or to invite professionals, you will need to know how much it costs to install a boiler in a private home. Installation price depends on the region of installation and the volume of the tank, but on average without the cost of materials, it is about the same:

  • capacity up to 15 liters, 1500 ;
  • a tank of more than 80 liters, 3000 ;
  • Capacity over 100 liters, 3500 ;
  • Installation of indirect water heater 200 liters, 5,600 ;
  • flow heater 5 kW, 2000

optimal place of installation

In order to properly install the boiler, it is recommended to place it as close as possible to the cold water riser pipes inside the apartment. This is done in order to shorten installation lines, reduce heat and head losses along the length.

Water heaters of small volume is allowed to strengthen the different walls, and for products with a tank over 80 liters is allowed to use only load-bearing brick or concrete walls. Even if their own weight of the storage water heater is negligible, together with the water and the pressure of the environment they create a large load on the wall. Vaillant System Boiler & Horizontal 300ltr Cylinder installation

Given the above, there are not many suitable installation areas in a small apartment, it is most likely to place the heater:

  • above the toilet bowl, if the size of the tank allows;
  • In the bathroom;
  • in the kitchen room under the sink for mini structures for 15 liters and under the ceiling for a volume over 30 liters;
  • in the kitchen on the floor to install a storage tank over 100 liters;
  • In the hallway. for compact horizontal models.

Materials and tools

Before installing the boiler, the home handyman should carefully study its instructions, especially the installation and adjustment section. It necessarily specifies the scheme and procedure for tying the boiler to the water supply, the requirements for the electrical system and its protection against overload, as well as a specification of spare parts that will be needed for installation work.

Basic tools, basic equipment and auxiliary materials that you need to buy, before you install the boiler with your own hands:

  • Water heater with anchors. manufacturer’s delivery;
  • safety valve. supplied by the manufacturer;
  • impact drill, for holes in concrete or brick walls;
  • Construction level, for a strict installation of the water heater, so that there was not aeration and bare heating elements;
  • set of locksmith tools with a hammer, pliers, screwdriver and wrenches;
  • Sealant, for example, FUM-tape;
  • plumbing hoses, 2 pieces;
  • Tees, according to the diameter of the outlet pipes, 3 pieces;
  • valves DN 15, 3 pcs;
  • electric conductor and circuit breaker according to the manufacturer’s data.

Fixing the water heater

To ensure that the boiler is stably mounted on the wall, the manufacturer has taken care of, it provides mounting hooks, anchors and strips included with the heater, which are professionally designed to hold it together with the water mass.

Fasten the special bar to the wall with anchors, and then hang the device on it.

  • Before properly installing the boiler, measure the dimensions of the tank.
  • Take the position of the structure on the wall in such a way that from the borders of it there is a gap of at least 70 mm at the top and at least 30 mm to the side, and the cover can be removed for repair work and in the process of maintenance.
  • Prepare a template for the holes, mark and drill them for fasteners. In the case where the wall has a coating, such as tile, it is first passed with a drill for tiles. After that the brick or concrete part of the wall is drilled with a powerful drill and a special concrete drill.
  • Dowels are inserted into the drilled holes and the anchors are screwed in or the anchors are inserted through the holes in the mounting bar and tightened with a wrench.
  • Hang the tank on the fasteners.
  • Use a construction level to check if there are no deviations. Vertical designs must not be mounted horizontally.

Connect to the water mains

When connecting the storage water heater uses a drainage pipe for the installation of the safety group of the device. It is a set of safety and non-return valves and fittings. Its purpose is to protect the water heater from emergency situations during operation.

The most common safety circuit of the boiler: an American pipe, a T-piece made of bronze is screwed on it, and the bottom branch is connected to the check valve, the water from the boiler did not return into the city pipeline. In case of low line pressure.

To the side tee branch an additional tee is connected to which a 6 atm safety valve is mounted. It resets the pressure of the medium in the tank in the case of an emergency, for example, when the water is overheated. This T-piece is also connected to a fitting to discharge water into the sewer.

The latest designs of heaters are equipped with a complex safety valve in which a safety valve and check valve are located in one body. After installing it, check that the safety valve opening is open, otherwise the protection will not work. In addition, the scheme may include a line for the heated water recirculation trimmer for the towel dryer.

Power connection

For the basic heating process BCH does not use electricity. In modern boilers, it is required only for the control and protection system. For the operation of the unit does not require high power, so the device is connected to the nearest grounded outlet. The cable to it is laid covertly, is connected directly to the fuse box or junction box.

To protect against over-voltage is used automatic double-pole circuit breaker at 20 A, which is installed in any convenient location.

To connect the indirect water heater, several schemes are applicable. The choice in favor of one of them is made depending on the heating system, boiler and boiler type, the required amount of hot water and the speed of its heating.

How to connect the boiler of indirect heating can be learned from

To choose a water heater boiler and learn the nuances of its installation will help our article at the link.

Advantages of separating the heating and hot water systems

Historically, systems with indirect heating must have a special boiler for heating the water heater, but with today’s high-efficiency boilers, the same boiler can now be used for both the heating circuit and the hot water supply system. However, when the room heating is not required, the boiler must still operate to provide heat to the hot water system.

Direct heating water heaters are designed solely to produce hot water, providing faster heating and response time compared to an indirect heating system that actually “heats water to heat water”. This increases the likelihood of heat loss in the boiler and associated piping between the boiler and water heater.

Water heaters are often installed close to where they are used, which reduces the energy required to run water over long stretches of piping and minimizes heat loss when distributing. This also helps reduce the length of dead spots in the system, sections of unused/redundant piping that pose a risk of legionella (bacteria).

Heaters used for hot water production don’t need a chimney and don’t have a direct connection to a gas mains. This makes them easy to install.

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