The popularization of the up-to-date surface heating/cooling systems is due mainly to the results of West-European researches that modernized the old principles with up-to-date montage solutions and solved the energy savings operation by hydraulic adjustment ensuring good thermal comfort feeling.

The surface heating can be fitted particularly to the low-inlet-temperature systems, because the surface temperature limits the upper temperature for the scaling. In case of gas boiler systems the inlet temperature could be reduced in underfloor heating circuit by a mixing valve. If heat pump is used, heating water should be entered into the circuit and it will work properly. Much better comfort is provided by radiant heat than by the convective heat emitters (radiator). The cooling can be solved with this kind of heat emitter, also giving radiant heat feel. The investment costs are typically higher than in the case of other heat emitters. It is an important motive to this case, that the precise scaling is not negligible. The hydraulics and the shaping of circuits with related aspects are very important in order to achieve proper operation.

Rehau - 1.png

Surface heating/cooling system

The surface heating systems - floor, wall and ceiling heating and cooling – ensure a pleasant and comfortable heat feeling with radiation energy due to low surface temperature and the even distribution of temperature. As against conventional heating systems, radiation balance evolves between human and surrounding surfaces, so optimum comfort can be achieved – with significantly lower room temperature.
In surface heating/cooling systems an optimum thermal comfort feeling can be achieved due to radiated energy with significantly lower room temperature.
The room temperature is reduced by 1-2°C, which is an annual 3 to 6 % energy savings. The surface heating/cooling systems are ideally combined with heat pumps. In addition, the surface heating systems can be used cooling; thus lower investment costs can be achieved.

Applications

The surface heating and cooling systems can be used for almost every building type. Basically, we can separate the surface heat emitters to two major groups:

•     Wet installed systems (floor substrate, plaster, coating)
•     Dry installed systems (gypsum-boardsystem)

The difference is that in the wet installed systems, the incorporation pipes are installed with some wet technological (gypsum or cement) coating, while in the other case pipes are already in pre- made panels (plastering is not necessary).

Careful planning - maximum comfort

After that the customer has decided next to surface heat emitters, there is an important aspect:

The surface heating/cooling system is not equal to a radiator system!

As opposed to the radiator system, the exact, professional sizing of heat emitters is essential. Because of the low inlet temperature, the primary side is often connected with renewable energy sources. The hydraulic sizing and accurate plan is the basis of optimally operation and low operating costs. We can only be sure of the proper operation of our surface heating/cooling systems at low operation costs if we decide on planning.

The advantages of surface heating:

    in terms of comfort
    in terms of economic
    against to the radiator
    against to the air-conditioning equipment

The advantages of surface heating in terms of comfort:

•     Optimal for space heating and cooling
•     Lower space temperature is enough due to heat feeling from radiation
•     There is not draught (wind velocity)
•     Free of noise, quiet operation (not moving, rotating parts)
•     Free of error possibility
•     Free of dust, pollen
•     Heat emitters are not visible because they are integrated in floor, wall and ceilings (no heating bodies)

The advantages of surface heating in terms of economic:

•     significantly lower operation costs
•     suitable to passive cooling
•     free of maintenance costs
•     corrosion can’t prevail – no need of changing heat transfer appliance, no waste in future

The advantages of surface heating in terms of economic:

•     High thermal comfort feeling due to the radiation balance between human and the surrounding surfaces
•     The cold effect of outdoor windows and doors of large surface can be significantly decreased
•     Heat distribution is more even within the room than in case of convective heat emitters
•     Heat distribution is more even vertically
•     Comfort feeling can be reached by heating with convective heat emitters at room temperature lower by 1 to 3 grade on Kelvin scale and will not overheat the area under the ceiling, out of the dwelling zone, therefore it is energy-efficient
•     due to lower room temperature people feel fit
•     Environment-friendly, due to applying heat outgoing, it can be combined with low-temperature or condensation boilers, heat pumps and solar collectors
•     low air stream due to low convective heat transfer so that dust and pollen does not circle in the air so the allergen dust load is reduced
•     no dust singe due to low surface temperature therefore it relieves the respiratory system – not only for allergy sufferers
•     no dust stripes due to low surface temperature and decrease in convection,
•     decrease in demand on cleaning against convective heat emitters of indented surface
•     generally there is no need of additional radiators, the user is free to furnish the rooms
•     free of visible heating apparatus, optically demanding rooms
•     it does not take up extra place in the room
•     it reduces risk of injury in nursery schools, schools, hospitals or retirement homes
•     the invisible register pipes can be found either with heat foil or an apparatus in heated up condition
•     every structural surface can be considered by the application
•     only small problem while furnishing in floor and on outdoor wall respectively no problem on the ceiling and inclined surfaces if applying the system
•     when applying low heating water temperature, the same as of surface heating, the investment costs are more advantageous as compared to the significantly larger convective heat emitting surface
•     surface heating and cooling systems are made exclusively of oxygen diffusion resistant pipes therefore there is no need of heat exchangers, secondary pump, expansion tank, other fittings and inhibitor
•     the simple and safe sleeve jointing technology known in water and heating conduits can also be applied in surface heating/cooling systems
•     panels with RAUTHERMS pipes sized 10.1x1.1 mm imbedded in prefabricated gypsum boards can also be used in case of wall and ceiling heating in addition to mounted-in-place registers, so there is no need of plaster coat
•     pipes can even be placed in constructional unit out, of or combined with the small inerting system of pipes and placed in plaster
•     mustiness of constructional units can be stopped or prevented
•     the possibility, as planned, is given for internal heat insulation and wall heating where the subsequent external insulation cannot be solved

The advantages of surface heating against to the air-conditioning equipment (Fan-coil, split):

High thermal comfort feeling since the energy exchange between human and cooling surface takes place on large surface and mainly by radiation
Comfort feeling equal to that of air-conditioner can be reached at room temperature higher by 1 to 2 oC, therefore it is energy-efficient.
It does not dry the air in the room. Due to fresh air supply the relative humidity can be maintained between normal values by the ordinarily necessary ventilation twice a day (early in the morning and late in the night). No over-humidifying of the air develops in the daytime. Over drying is impossible in case of surface heating against split and FC equipment.
There is no draught effect that originates from cold inlet air
There is no Sick-Building effect (low air temperature and high wind velocity cause it)
Legionella disease caused by fungus and microbe can’t evolve
There is no mechanical structure within the building, so it is free of noise
There is no heat and general feeling problem caused by the alternating draught and noise effects
Heat feeling distribution is more even within the room
the temperature of the room air is more even in vertical direction
there is no machine, no machine error in the room, so it is free of maintenance, no need to clean the filters, life of the system increases
Free of water drain system
Free of dust load due to low air motion
It is healthy since there is no sudden cold effect in dog days when entering the room and there is no sudden heat effect when leaving the cooled room
It is energy-efficient, without condensation, therefore there is no difference between the whole and the perceptible cooling efficiency
Free of visible internal appliances and disturbing external appliances on front of the building, therefore optical buildings and rooms can be formed
Environment-friendly, since it can be combined with heat pumps or passive cooling solutions
as demanding solution, development of four-pipe heating-cooling distribution system is possible 

From the point of surface view we can differentiate floor, wall, ceiling and other heating systems (such as inclined plain, heated bench, heated pseudo-fireplace). Characteristics and important specialties hereto please find in subparagraphs below.
Of course, it is unworthy and unnecessary to define which surface is to be used but it must be emphasized that the appropriate surface or combination of surfaces should be selected for the given task and local conditions.
Naturally, there are standpoints that can be and should be considered when defining sequences.