The majors features of the undefloor heating is very low temperature of heating surface and high room temperature oscillations. The temperature of heating surface should not exceed 35°C. Underfloor heating ensures you thermal comfort which is difficult to obtain by radiator heating. Walking on warm floor is simply speaking - singularly pleasant.
Heating the floor speeds up evaporation of the water on it which is a significant benefit while speaking about bathroom, kitchen and entrance hall. Of course for some still the biggest advantage of UFH is its practically invisibility and the fact, that it does not take up room's space. Last, but not least is it worth to remember that UFH is extremely effective when heating big and open spaces/rooms.
Most of thermostats available on the market work as ON/OFF device. Using this type of thermostat in UFH system results in overheating or cooling of the room. The solution for high thermal inertia distinctive for UFH is to use devices with TPI or PWM function.
How does it all work?
TPI (Time Proportional & Integral) is a self-learning, time-proportional algorithm. This method of control applied in SALUS thermostats is a great example of advanced technology using to achieve better control results and faster responding time (in comparison to conventional solutions). TPI type of regulation ensures economical system operation through more accurate temperature maintenance during controlling process and limits overload conditions. In addition to the exact and stable room temperature, the advantage of this system is the minimization of energy consumption and significant savings
PWM (Pulse Width Modulation) system - by continuously comparing set temperature with actual temperature, the lengths of opening times for the valve actuators are regulated in such a way that the temperature is almost completely prevented from exceeding or falling below the set temperature. In this way, the required temperature setting is regulated in a precise and convenient way.
Radiator heating called also ' traditional' heating give us an opportunity to increase quickly the temperature in the room. The air heated by radiator becomes warmer just after a few minutes after turning it on. If the high temperature in the room is not needed any more, we can close the radiator valve and reduce it, thereby saving the energy. When we want to change the temperature quickly we should use the radiators with low water volume. It's recommended to put them in bedrooms where quick temperature changes are usually desirable before sleep.
Underfloor heating is not also very appriopriate for rooms that we use occasionally, for example guest rooms or the ones where the floor is partially covered by furniture. It is adviseable to have one radiator in the bedroom anyway (even if we have decided for underfloor heating system) because it is always good to put a towel on it to let it dry.
Underfloor and radiator heating
If we plan to combine underfloor and radiator heating, we should remember about characterisctics of particular systems. The tempareture of heating factor in the underfloor system is lower than in the radiator system (usually remains at the level around 35°C while the water in radiators can be even 80°C; the temperature of the floor in the rooms should not exceed 29°C and 35°C in the bathrooms). We should not forget that the way both system work is quite different. Underfloor heating is characterized by huge room temperature oscillations which means that it takes much longer for the floor to warm up than radiators. In the contrary to the radiators which become cold short after turning off the heating, the undefloor heating remains warm for at least few hours.
The investors and installers usually choose to install the underfloor system on the groundfloor and radiator on higher floors. It is justified if the usable floor space (kitchen, diningroom, bathroom) is located on the groundfloor and bedrooms on the 1st floor.
Radiators are particullary recommended for smaller rooms which are not in use during the day. Mixed system is also a good solutions for building that are more sophisticated or complicated from architectural point of view - with big balcony windows or glassed terraces which may cause additional heat losts.