The ceiling radiant panel system is widely used in offices and, more generally, in large functional buildings such as hospitals, shopping malls, schools, universities, airports or stations.

In these cases, the suspended ceiling is made up of metal panels (7) that can be inspected completely similar to those usually used in these buildings, but with hydronic circuits applied to the upper part and possibly an insulating layer towards the plenum. The hydronic circuits consist of metal or plastic pipes and metal thermal diffusers that exchange heat between the pipes and the metal surface of the false ceiling. The series of radiant panels are powered by distribution manifolds installed above the circuits served.

The system is invisible and uses the entire surface of the ceiling as a large terminal for the heat exchange (prevailing as radiation). As in the case of the floor system, the ceiling radiant panels only handle the sensible heat loads; in general, the ceiling solution offers a higher yield in cooling.

The ceiling radiant system shown in the example is used for heating and cooling the rooms of a functional building. The distribution is made with a 4-pipe system that make available both fluids at the same time to heat or cool the room.

This type of distribution can be advantageous when it is expected that the thermal loads can vary greatly during the same day or depending on the different exposures of the building. In this application, the air renewal and dehumidification functions are performed by a system with air centrally treated by an air handling unit and distributed in the rooms by means of ducted systems and diffusers. As an alternative to the diffusers, and in the absence of insulation towards the plenum, the microperforation present on the metal panels can be used for the diffusion of renewal and dehumidified air in the rooms.

Control with Ekinex

Room air temperature control is carried out in each zone or room by means of a multisensor (D) in combination with the EK-HE1-TP actuator (A), which controls the servomotors of the zone valves that regulate the inflow of hot or cold heat transfer fluid to the radiant panel arrays. By measuring relative humidity, the multisensor (D) can also calculate the dew temperature and send it via bus to higher-level systems (BMS) through appropriate gateways.

Where necessary, the multisensor (D) can receive a measured temperature value from an Ekinex EK-E13-TP series pushbutton (C), normally used to control other functions such as lighting or shading, to make adjustments based on a weighted temperature value. This can typically be done in large or volumetric rooms, where the temperature value measured by the multisensor is not fully meaningful of the general temperature conditions in the room.

The EK-CD2-TP input interface (F) provides for the acquisition of signals from anti-condensation probes (5) and window opening contacts (6). The anti-condensation probe (5) is installed in contact with the first heat exchange element served by the hydronic circuits so as to promptly detect any condensation when the system is in cooling mode and cause the actuator-controller (A) to close the corresponding valve (4), bringing the system to safety.

To reduce energy consumption, the operating mode can be automatically switched according to the presence or movement of people within the zone by means of the real presence sensor EK-DF2-TP (E), calling up temperature attenuations of opposite sign in the heating and cooling conduction modes.

Focus on the multisensor

The Ekinex multisensor (F) is a complete device for controlling room air conditioning that combines many functions usually distributed among several sensors and different controllers. The device measures temperature, relative humidity and air quality (parameter: equivalent CO2 concentration in ppm) using the integrated sensors, with the possibility of sending values to the KNX bus, and can also act as a controller for each of the measured parameters.

With a single compact device it is therefore possible to control both the thermohygrometric conditions and the quality of the room air mass. In special cases (large or high rooms, in the presence of strong asymmetry in the temperature distribution or when the device is installed in an unsuitable position), the room air temperature can be controlled by using a weighted average between two temperature values: the first measured by the integrated sensor and the second received by the KNX bus.

Two independent thresholds for relative humidity and three thresholds for CO2 concentration can be configured. To implement automation logic, combinatorial functions such as AND, OR, NOT and exclusive OR are available; thanks to these functions, it is possible to use the information available on the home automation system to control air renewal according to the actual need (DCV or Demand Controlled Ventilation).

Versions

EK-ET2-TP with relative temperature, relative humidity and CO2

EK-ES2-TP with relative temperature, relative humidity and CO2 and TVOC

LEDs

The eight integrated LEDs (with light guide), positioned on the sides of the front cover, can be configured to indicate the active operating mode of the heating system (heating or cooling), the concentration of CO2 (equivalent) and the activation of the dehumidification or humidification function.