A field study on occupants' thermal sensation vote in a test room equipped with trombe wall

Trombe walls have emerged as energy-efficient and sustainable solutions for providing thermal comfort. They make use of solar energy to passively deliver heat, reducing the need for traditional heating systems that rely on non-renewable energy sources, and contributing to the mitigation of carbon emissions. During the day, a Trombe wall absorbs solar radiation and heats the air that lies between the glass cover and the wall. Heated air rises and circulates through the vents positioned at the top and bottom of the wall supplying predominantly convective heat to the occupied space. In contrast, during the night, the vents are closed to prevent heat loss, enabling the wall to gradually release the stored energy into the occupied space, thereby providing mostly radiant heat. In addition to sustainability and energy efficiency, Trombe walls may offer better thermal comfort than traditional heating systems, thanks to low air speeds and radiant heat. To evaluate their performance in terms of thermal comfort, it is essential to assess the Predicted Mean Vote (PMV) and Predicted Percentage of Dissatisfied (PPD) indices, which quantitatively measure human thermal comfort by taking into account several factors, including air temperature, radiant temperature, air velocity, humidity, and clothing insulation. Although PMV and PPD are widely used for assessing comfort, real occupant votes would be more reliable. This study aims to evaluate a Trombe wall-installed test room's thermal comfort performance located in Cyprus through real occupant votes during daytime use. Indoor and outdoor environmental conditions were monitored to determine the correlation between comfort levels reported by the occupants and the recorded conditions. Participants completed a survey on their thermal sensation, which was converted into a 7-point scale using the Fanger model for quantitative and qualitative analysis. Although the mean value of the occupants' votes did not entirely fall within the acceptable PMV and PPD range suggested by the standards, the deviation was not significantly high. The thermal sensation votes indicated that the conditions were slightly warm.