Designing a manifold node
Simplify the comb assembly will help its pre-made scheme. Having at hand, even an amateur sketch, you will be insured against many mounting errors. But a well thought out scheme of a floor heating collector, drawn up by a professional, must already take into account a number of parameters and practical points. The most important among them are:
- the number of heating branches (loops);
- Definition of the characteristics of consuming devices. diameter and meterage of pipelines of circuits, as well as hydraulic losses in them;
- type of heating boiler, its main operational features. thermal capacity, circulation pump capacity, the temperature of heating fluid;
- Existence of additional equipment in the heating system. storage and damping tanks, pressure gauges, thermometers, safety groups, water posts, etc.п.;
- The need to provide the ability to scale. to connect additional circuits, to improve the control system. to install on existing control elements of automation devices, as well as blocks that provide remote access.
IMPORTANT! A professional floor heating manifold connection diagram doesn’t just give you an idea of which tap is responsible for a particular area. It allows you to arrange the pipelines in a more orderly manner, and further facilitates the setting and management of the heating system.
Overview of major manufacturers of heating manifolds
REHAU (Rehau). the market leader in heating systems produces manifolds for underfloor heating systems made of brass Ms 63:
- HKV, for 2 to 12 circuits.
- HKV-D, similar to HKV, additionally equipped with flow meters and valves on the supply pipe, and a control valve on the return pipe.
Manifold REHAU for heating is designed for a maximum operating temperature of 80 C, and medium pressure. 6 bar. It is distinguished from other brands by its soundproof galvanized brackets.
On the market Oventrop sells shower head for underfloor heating, made of instrument steel, the maximum parameters of the medium: pressure. 6 bar, temperature. 70 C. It has air vents, connection pipelines to the radiators are threaded G3/4, as the right and left connections.
Valtec produces a manifold for radiators and floor heating. The flow part of the manifold is equipped with a flow meter and an end pipe with float valve for bleeding the air from the network, shut-off valve and drain cock.
Millennium manifold groups are made of stainless steel, complete with thermostatic valves to regulate the heating process. Manifold heating fluid parameters:
- The pressure. 10 bar.
- The maximum temperature. 100 C.
- The availability of integrated valves provide a wide range of application of devices: with mixing units, electro-thermal actuators and sensors.
Please note! It is noteworthy that the design allows you to install air-conditioners on either side of the collector.
Designing a makeshift collector
The first step in the work to create a homemade distribution manifold is its design. Competently created project will greatly simplify the work and will create a quality welded manifold for heating, which is optimal for specific conditions.
Before you assemble a heating manifold, you need to assess a number of parameters of the heating network of the building:
- Number of heating circuits in which it is necessary to supply the heating medium;
- The number and parameters of the heating equipment (power, heating temperature, pressure, etc.).п.);
- The necessity and possibility of further integration of additional elements into the heating system;
- the number of additional elements of the system (pumps, valves, shut-off valves, etc) will not be excessive.).
Next, you need to carefully consider the peculiarities of the connection of different circuits to the distribution manifold:
- Electric and gas heating boilers can be connected to the manifold from above or below;
- If there is a circulation pump in the scheme of the heating system, boilers may only be connected from the end of the collector;
- Indirect heating boilers and solid fuel boilers can only be connected to the manifold from the end;
- The supply of each heating circuit is connected to the manifold from above or below.
In order to accurately and clearly see how to assemble a heating collector, you should depict a project on paper or print it if the scheme was created on a computer. A clear picture with observance of scale and the required number of elements makes it possible to check the work in order to prevent installation errors.
In the scheme you must necessarily put the dimensions of each part of the collector. For example, the distance between supply and return nozzles should be about 10-20 cm. larger or smaller deviations will complicate maintenance of the device. A similar distance should be between the supply and the return part of the manifold.
The main quality of the collector is functionality, but do not forget about the fact that the device must be fairly compact and decent-looking. That is why, if there is an opportunity to make the device more accurate. it is worth the effort.
Some owners of private homes prefer to install a collector for underfloor heating with their own hands. Once a special cabinet is ready, the coolant supply and return pipes are installed in it. The first of these supplies hot water to the system from the boiler, and the second. Collects cooled coolant and returns it back to the place of heating.
Myson Flow Meter Cleaning
To water flow was continuous, perform the installation of a circulating pump in the heating system. At the ends of the supply and return pipes put stop valves. Thus, if you need to turn off the heating in one of the rooms or in a certain part of the building you need to close these two taps, which will not affect the heat supply to the rest of the rooms in the house. To connect the plastic pipe to the metal valve use compression element. fitting.
Assembly with three-way valve and pump
Three-way valve. device designed to mix the two streams of heat transfer medium. heated and colder water coming from the return pipe. Inside it there is a sliding element that regulates the intensity of flow of coolant. It can be controlled by a thermostat, or by a thermostat operating in electronic or manual mode.
Schematically, the mixing unit on the three-way valve looks like this: its outputs are connected to the hot water and return flow, and the output going to the supply comb. Behind the valve the pump is installed, which directs the coolant to the supply pipe. Somewhat further away there is a temperature probe from the thermostatic head located on the three-way element.
Functions such a mixing manifold node for underfloor heating with a pump as follows:
- The hot water is supplied by the heating boiler. It initially flows through the valve without any flow rate.
- A temperature sensor informs the valve that the water temperature exceeds the setpoint temperature. The three-way element opens the heating medium flow from the return pipe.
- The system then continues to run in this state until the water temperature matches the setpoint.
- The valve stops delivering cold water.
- The system then functions until the heating medium is too hot. Then the water mixing starts again.
Such a scheme has a big disadvantage. There is a possibility that the underfloor heating circuits can malfunction and the hot water starts to flow without any flow. As plastic pipes are usually laid in the screed, they will deteriorate if exposed to higher temperatures for a long time. But this defect in the circuit can not be eliminated.
In the diagram, which describes the principle of operation of a floor heating manifold equipped with a three-way valve, you can see the jumper. bypass. It is designed to eliminate the operation of the boiler without coolant. Such situations arise when the stop valves on the manifold is closed.
If there is no bypass, the unit can overheat and become completely unusable. If it is available, the water coming from the supply is directed to the boiler inlet via the jumper. As a result, overheating will not occur and the system will function as intended.
What is a manifold assembly in heating
The manifold is an assembly of plastic (rarely metal) pipes, valves, gauges, valves, fittings, and other accessories. The manifold is designed to mix the coolant coming from different heating circuits, and further distribution of the same. As a result of mixing, the temperature of the liquid is equalized, respectively, the temperature in the heated rooms remains constant and stable.
The quality of the underfloor heating system depends on the proper assembly of the manifold.
The operating principle of any heating system is well known. the coolant cools down after passing through all the circuits and pipes, and under the influence of a circulating pump or natural circulation comes back to the collector, where it mixes through the return pipe (return). Proportion of cooled and heated coolant is regulated by special valves, its temperature is controlled by heat sensors, weather sensors and pressure sensors. If the heating system is too long or the house layout does not allow for natural circulation, a circulating pump is connected to the collector.
Typically, the apartment or house radiators are connected to the boiler, sometimes self-made registers. In any case, the temperature of the coolant in the radiators must be within 70-95 0 C. When connecting the system “warm floor”, which is often done in modern apartments, the temperature of the coolant should not exceed 30-55 0 C. According to health regulations, the maximum temperature of the floor heating should not exceed 30 0 C, otherwise the floor covering (linoleum, wood-fibre board, PVC tile) will warp, the air in the room will be dried up, and walk on the hot surface is not very comfortable.
Therefore, in such cases, a manifold is included in the system. because the temperature difference in the central heating system and in the floor heating system is significant, and the boiler gives only one value of temperature. Another reason to install a manifold. the floor heating has a large length of pipes. Consequently, the total pressure in the system will drop. To maintain the pressure at the required level it is necessary to install a circulation pump, which is included in the design of the manifold.
Mechanism of operation of the node
The mixing unit performs not only the function of regulating the temperature of the water in the line. It is also responsible for its normal movement through the circuit. The appliance includes a safety valve and a circular injector. The last element ensures normal circulation of the medium in the underfloor heating system at the required speed. This point is important for complete and uniform heating of the surface.
The safety valve is responsible for mixing the water in the circuit. When boiling water enters the inlet, it opens the flow from the return circuit until the hot water mixes with the cold carrier from the. Then it stops the flow of boiling water.
In addition to the two main components, the manifold may include conductor and shut-off valves, bleed valves and bypass, which acts as an overload protection for the device. These elements may not always be included in the device. Therefore, the manifold for underfloor heating with their own hands can be installed in several different ways. Here it depends on the result you need.
It should be noted that the mixing node is always mounted in the area before entering the heating circuit. However, its immediate location can be anywhere. In some cases, it is advisable to install the device directly in the same room where the system runs. This is usually done in apartment buildings. Sometimes it is appropriate to put it in a common boiler room. This option is probably the preferred one for private residences. If there are several rooms with underfloor heating, the distributors are usually placed in each room, or a common collector is arranged in a suitable location.
All differences in the principle of operation of faucets are determined by the safety valves. The most common of these are considered to be two- and three-position valves.
Collector unit is a special unit through which the mixing and transmission of the coolant from different circuits of the heating system takes place. As a result of this action, the temperature of the water circulating through the pipes is equalized. This achieves the stability of heating. As a result, the air temperature in the room will reach a certain level, which is set from the control center.
The manifold circuit is a complex system, which can work due to the presence of two pipes:
- feeding. It comes out of the boiler and delivers the heat transfer fluid to the structure of the water underfloor heating. It is characterized by high temperatures, which can reach up to 90 ° C;
- the return. It is designed to move the waste chilled water from the underfloor heating back into the system. This fluid is reheated in the boiler, which provides a constant circulation.
Installing underfloor heating in the apartment, you need to know how to properly connect the manifold in the system. After all, the circuits are not connected directly to the boiler, but through manifolds, pumps and sensors.
- A plug is provided for the outlet of the distribution manifold. In some cases there is a branching network, a tap for drainage and a device for removing air from the pipes of the underfloor heating.
- Such a design is done on the supply branch of heating and return branch. For underfloor heating, it is recommended to arrange not one, but a pair of such combs and, accordingly, related devices.
- Mixing manifold is placed in a special cabinet so that unwanted persons do not have access there, and maintenance and parameter changes were made by one person. The cabinet can be locked and can be made in internal or external version.
- Make a collector with their own hands need to take into account the number of connected heating circuits and the material used to manufacture the device. If there are two branches of floor heating with different required temperature conditions, the collector is connected to supply water of different heating in these branches. If the pipes are long, an additional pump is integrated into the system to create the necessary pressure.
- Each outlet of the pipe from the manifold for underfloor heating must be equipped with a ball valve. It can be used to turn off a number of heaters without stopping the entire system.
- On each floor of the main riser there should be placed supply and return headers. From them the pipes go into the floor or run along the walls to the radiators. In the case of underfloor heating, when the pipes are embedded in the screed, it is mandatory to install a device to trap and bleed air from the system.