When looking for a water-based underfloor heating system, it can be difficult to know which type best suits your needs. There are several different types of water-based underfloor heating. Each type has its own unique advantages and can be designed to meet specific requirements. Read more in this blog post. high-temperature systems, low-temperature systems and block and district heating.
High-temperature underfloor heating system
Is the supply temperature of the water from the heat source (for example central heating boiler) between 65°C and 90°C , then we speak of a high-temperature system Underfloor heating (HT system). This is too hot to flow directly into the underfloor heating pipes. In these situations, it is therefore necessary to mixing distributor to use, which is equipped with a circulation pump .
Mixing distributors are equipped with a thermostat knob which regulates the temperature that flows into the pipes. The overly warm supply water is mixed with cooled return water from the pipes. The mixing allows pressure loss This type of distributor is therefore equipped with a thermostat knob as well as a circulation pump (a closed distributor). This ensures that there is always a optimal flow is in the heating pipes.
Low-temperature underfloor heating system
Is the supply temperature of the water from the heat source (e.g. heat pump) between 30°C and 65°C , then we speak of a low-temperature system Underfloor heating (LT system). A distinction is also made between open LT systems (low-temperature system) and LTV systems (low-temperature heating system).
Open LT system
In an open LT system the supplied water has direct access to the correct temperature . This is maximum 45°C . In this situation, a open distributor (without pump). The pump of the primary heat source (central heating boiler/heat pump) provides the circulation of the hot water through the pipes of the underfloor heating and any other parts of the central heating system.
For optimal flow through the heating pipes, open distributors must be connected to a supply line immediately minimum diameter of 22mm if metal pipes are used. If flexible plastic pipes are used, then the Minimum diameter 25 mm . The internal diameter must be at least 20 mm to prevent any pressure loss.
LTV system
In an LTV system the water supplied is maximum 65°C . That is just too hot to flow directly into the pipes, but too cold to use a standard mixing manifold. That is why an LTV system uses a Adjustable manifold with circulation pump . This manifold is suitable for heat sources such as central heating boilers with a supply temperature from 40°C , but also for HR boilers with a modulating burner or systems that use a buffer tank .
The control valve on the distributor allows cooled return water be added to the overly warm supply water. This can pressure difference can be created, causing the circulation pump to draw in more or less supply water. This allows you to regulate the water inflow on the distributor.
Block and district heating
Block and district heating are collective heating methods. With block heating, multiple homes are heated with one collective boiler . This is particularly evident in apartment buildings and office complexes . With district heating, homes and buildings are heated via a underground hot water pipes . The heat used is often residual heat released from power plants or waste incineration plants. A technique increasingly used for district heating is geothermal energy. In this technique, hot water is extracted from deep underground. pumped up .
The supply temperature of block and district heating is too high to allow the supplied water to flow directly into the underfloor heating pipes. Therefore, a Mixing manifold with circulation pump . Unlike a HT system, a mixing manifold used in block and district heating must be equipped with a non-return valve and temperature return limiter (RTL tap) to meet the requirements of district heating.
This type of mixing distributors are equipped with a thermostat knob . This controls the temperature of the water flowing into the pipes. By heating the supply water to a higher temperature, mix with cooled return water from the pipes, the mixing manifold ensures that never too hot water flows into the pipes. The pressure loss caused by mixing is resolved by the circulation pump. The circulation pump ensures that there is a optimal flow through the heating pipes.
