A mixing unit or collector for a warm floor is installed in order to regulate the circulation of the heat carrier and the level of its heating. In addition to the main function, this device helps to measure the pressure in the heating system, controls the correct supply of the heat carrier and eliminates excess air from the heating circuit. If water-type warm floors are installed in several rooms, you will not be able to do without such a device. It is worthwhile to study the types of devices and the principles of their operation in advance in order to make the right choice.
The principle of operation of the collector for underfloor heating
The mixing unit helps to realize the supply of the heat carrier without the need to be connected to the common header of the boiler room. A standard device of this type has a simple structure, is a group of several devices and can be operated with a two-way or three-way valve. If the heating system is of a mixed type, such a unit is supplemented with a circulation pump.
The second pump is needed to cover all the loops of the floor covering, while the first is responsible for the operation of the radiators. To determine the selection of the valve, you must first calculate the throughput for the water floor heating circuits and find out the temperature limits for the heat carrier. For the middle and southern lane, a lower limit of up to 30 degrees or lower is sufficient, for the northern one - from 35 degrees.
Assembled circuit
The two types of collectors work in different ways. The three-way valve combines two water flows: hot and cold, which come from a return type pipeline. It contains a movable sector to regulate the intensity of the water flow. The part can be controlled using a thermostat or a manual or electric thermostat. During operation, the heated water supply with return flow and the outlet path for the manifold are connected to the valve openings. A pump is installed behind the valve for water pressure towards the main manifold, as well as a temperature probe. The device operates according to the standard algorithm:
- The heated water comes from the boiler and for the first time passes through the valve in an unchanged state.
- The information from the sensor about the excess temperature goes to the valve, which opens the addition of chilled water.
- The system operates at this stage until the liquid temperature approaches the optimal value.
- The cold water supply ends with a valve.
- The operation of the system continues until the water heats up to the maximum temperature, after which the admixture is activated again.
The only drawback of the three-way valve is that heated water can be supplied without mixing directly in case of malfunctions. If polymer pipes are installed under a warm water floor, they may become unusable due to exposure to boiling water.
Development on a two-way valve is considered more reliable, during which water never enters the circuit directly from the boiler. This effect is achieved by a balancing valve installed between each return and supply line. He is responsible for the amount of chilled water and can change the value depending on the required temperature using a hex wrench.It is worth installing a two-way type controlled valve with a temperature sensor in the distribution unit. The intensity of the heated water supply will change if the sensor is installed after a pump capable of directing the heat carrier into the comb.
A distributor with a two-way valve mechanism is capable of heating no more than 150-200 sq. m of warm cover. Despite its reliability, it has low performance.
Collector types
Collectors are divided into several varieties depending on their price, set of functions and material of manufacture. The most expensive and reliable assemblies are made of stainless steel. Brass manifolds are included in the middle category, they can last a long time if they are made of high quality and durable alloy. Inexpensive devices are made of polypropylene, they are only suitable for low temperatures. The device itself is externally a part of a pipe with the required number of branches; it can have a simple or complex configuration.
The list of common options includes collectors:
- with fittings for connecting circuits;
- with integrated cranes;
- with valves for water regulation.
There are budget options - assemblies from double distributors: return and supply. These instruments may contain additional parts such as a flow meter, mounting holes or taps.
How to make a choice
When choosing, first pay attention to the number of circuits required for connection. When purchasing a collector for water-based flooring, it is best to purchase a comb with extra headroom for one outlet. It will be needed if it becomes necessary to split a long circuit into two branches or connect additional equipment.
You also need to decide on the type of material. The most reliable devices are made of stainless steel, natural bronze or brass. The best option would be mixing units from renowned manufacturers: Valtec, Stout or Tim.
Self-assembly of the device
The mounting scheme is most often already present in the kit of any collector device. You can assemble a collector for a warm floor yourself if you follow the step-by-step instructions. The device is mounted horizontally on a wall or in a pre-prepared niche, leaving free access to the main arrow of the heating pipes. Next, you need to connect the collector to the boiler so that the heat carrier is supplied from the bottom, and the return goes along the top. After that, a bypass valve with a temperature limiter is mounted, a distributor comb is placed behind it.
Pipes running inside the floor are fixed from above, coming from the heating system - from below. After installation, the device must be configured according to the rules, check how tight all the connections are by connecting the collector group to the main pump. With the help of a pump, the pressure inside the system is injected, after which the water circuit must be left in this form for a day. If all the indicators have been preserved, the installation was carried out according to the rules, the unit can be operated.
Connecting underfloor heating to a collector device
Additionally, a protection system is installed, consisting of a bypass and an air valve at least at arm's length. After a complete installation of the collector, all pipelines from the warm floor covering must be connected to it. Then they check the tightness, quality, and reliability of all joints.It is worth starting the system for the first time before starting the installation of the main coating, it is important to check the quality of heating for all lines, inspect the pipes for the level of leaks. Only after that they begin to mount the topcoat.
For the device to work effectively, it must be correctly adjusted taking into account the length of the circuit and the heating load. For this purpose, the valve is placed in a predetermined position according to the circuit number and the number of revolutions.
Do you need a collector
The main disadvantage of the device is considered its high cost, but it must be taken into account that without it, warm water-type coatings will not be able to function normally. This is only possible if the cover consists of one heating circuit. In modern underfloor heating, the length of pipes for laying cannot exceed 70 meters. Since this amount will only be enough for 7 square meters of area, for a medium-sized room you will need at least three contours.
Most often, warm water-type coatings are installed in all rooms of an apartment or house. In this case, it will be necessary to install the collector to evenly distribute the supply of the heat carrier. If we are talking about one small room, the collector may not be purchased. It must be remembered that without this device, the coolant will be supplied with the temperature as in the general heating system. Also, without it, it is impossible to remove air locks and control pressure.
