Features of the scheme of a single-pipe heating system with a lower wiring

There are two main ways to place the pipes of the water heating system, their connection with boilers, heaters in one design - with one line (pipes) and two, as well as with top and bottom connections. Consider single-pipe heating with wiring from below.

Device

The schema includes the following components:

• the main element is a boiler (on gas, solid fuel);
• radiators - cast iron or modern bimetallic;
• for pressure stabilization, expansion compensation. It eliminates too much heating and water hammer;
• drain taps, piping, shut-off valves - for organizing water supply;
• bypasses.

Advantages and disadvantages

The wiring of risers from below means that the pipes through which liquid circulates through heating devices are located at the lowest point of the room: at floor level, under the floor, in basements and plinths.

The advantages of a one-pipe system are economy (less labor and materials), ease of installation and aesthetics.

The heating circuit with a lower wiring has several disadvantages. Firstly, the closed water flow does not allow turning off one radiator or adjusting its operation separately - this is possible only by turning off all devices and the whole line.

This also explains the difficulties in fixing a leak or repairing a radiator - you have to drain the entire coolant. All these problems are solved with the help of bypasses or bypass spare lines.

Comparative analysis

In a single-pipe line, there is only one pipe - the supply pipe. A two-pipe system has not one, but two pipelines: supply and return. Between themselves, they are connected by heating devices and radiators as jumpers. Each scheme has its advantages: a two-pipe one is more convenient to manage - liquid of the same temperature flows into each radiator, so they heat up evenly around the entire perimeter.

A single-pipe system with a bottom connection is only with forced circulation, with the exception of one exception, when a gravity method is organized in the presence of an accelerating manifold. Then the liquid from the boiler is directed vertically down, then to the collector, and then through the devices connected in parallel into the circulation ring.

The differences between the upper wiring and the lower wiring are as follows: it does not have bypasses, the supply pipe is connected at the top of the radiator, the outlet pipe is at the bottom. In this case, the radiators are connected from top to bottom, water is also supplied. This scheme is more suitable for the natural circulation option and does not have a supply riser. Valves and taps are not mounted on the batteries, therefore it is impossible to adjust the temperature regime separately in any room.

Principle of operation

A single-pipe heating main is not divided into a supply and return pipeline. The coolant moves along a closed ring: it leaves the boiler and returns through one pipe. In such a scheme, radiators and devices are arranged in series.

Liquid enters each functional element in turn. This method of movement of the coolant causes a gradual decrease in temperature during its alternate movement through the batteries of the system - the next heating device is always slightly colder than the previous one, and the last one is the coldest.

Cycle and types

In the scheme we are considering, both risers - supply and return - are located in the basement, basement. The feed is connected to the main line from below. In a multi-storey building, a direct riser moves the coolant in turn to each floor, where it is distributed sequentially over the radiators and gives off heat. Such a cycle ends with the return (lowering) of the cooled liquid into the boiler. The heating of the battery can be regulated by a thermostat.

During circulation, a certain amount of air inevitably gets into the pipes, it can gradually accumulate, so it is removed through special valves on the top floor - this is a closed system (open circuits are most often inherent in the upper wiring). Pipes can be placed both vertically and horizontally. In general, a single-pipe system can be open, with horizontal and vertical pipes.

Bypass and Troubleshooting

Radiators with lower risers can heat up unevenly - as a rule, the upper part heats up less. The bypass closes the circulation of the coolant. Simply put, this is a piece of pipe connecting the risers so that the hot liquid from the supply goes immediately to the return line.

There is another way to eliminate the shortcomings. So, heating devices cut into the main line in parallel, are supplied with valves and control valves. As a result, the speed of the coolant increases, the temperature difference is eliminated, and it becomes possible to repair the device without draining the liquid. Such a connection is especially necessary when the room is too hot.

The bypasses have shutoff valves and can be turned on and off. Such a device can be independently welded from the remains of pipes. The circumference of the bypass must be smaller than that of the risers - otherwise the water will not be distributed between it and the radiator, but will completely enter the return line.

A thermostat is mounted in front of the entry hole at the extreme segment of the batteries - this will make their management even more convenient.

Installation

The creation and equipment of a single-line scheme with pipes from below to the radiators is carried out in several stages. To do the procedure with your own hands, you will need certain tools.

Tools

For installation you will need:

• adjustable wrenches, screwdrivers, hammer;
• for sealing joints - taklya, sealants, seals;
• for fixing devices and pipes - fasteners, brackets, nuts, bolts;
• for pipe connection ⎯ welding inverter, threading tool, metal cutting and grinding equipment;
• to create the necessary holes in the walls and metal - a drill, drills.

Installation order

The installation of elements is carried out in the following order:

• the supply and return ends are connected to the corresponding openings of the boiler. It is better to immediately install special filters so that the boiler does not become clogged with rust, small debris, impurities;
• cranes, valves, Mayevsky air valves are mounted;
• radiators are fixed on the wall under the windowsill with dowels, brackets. The distance from the floor is 10–12 cm, from the wall - 2–5 cm, from the window sill - 10 cm;
• the last step is to connect the boiler to the water supply and test run to detect leaks or possible malfunctions.

The boiler is the main device in the circuit, it is located at the lowest point in the recess. This does not have to be a basement - a small recess in the floor will do. The surface should be as flat as possible, a concrete screed is a good option. It can be tiled for aesthetic reasons.

For most boilers, a chimney is required, which is made from a pipe of a suitable diameter. The joint of the pipe is finished with refractory material. Such a pipe is connected to a boiler made of corrugated metal, strong enough not to burn out. Metal pipes can be connected directly to the boiler, but they must be a little thicker at the bottom to withstand high temperatures.

The expansion tank must be installed at a height of about 3 meters. This device is the highest point of the heating line. When installing pipes, it is desirable that there are as few bends in the heating as possible: they impede circulation, which is especially important for a one-pipe system.