HI-02-06-4 -- Field Measurements of Operative Temperatures in Buildings Heated or Cooled by Embedded Water-Based Radiant Systems PDF

The performance of radiant heating systems (floor heating, ceiling panels) is relatively well documented. Water-based systems, where pipes are embedded in the building structure, are now being increasingly used for cooling purposes. Several theoretical studies based on the use of computer simulations have been published, but very little has been reported on the actual performance in existing buildings. There are still uncertainties on how such systems operate and on how well the space temperatures are kept within the comfort range under varying external and internal loads.

To study this aspect, field measurements of thermal comfort conditions were made in several buildings with radiant surface systems: floor, wall, and systems with pipes embedded in the concrete slabs between each floor in a multistory building. Long-term measurements of operative, air, surface, system, and external temperatures have been carried out. The present paper present the results of the measured operative temperatures.

The analysis of the data shows that, for the major part of the time of occupancy, the operative temperature is inside the comfort range. The data show an increase in space temperature during the day, which is counterbalanced by a corresponding decrease during the night. This study shows that hydronic radiant systems in many buildings are an interesting alternative to full air-conditioning systems for obtaining acceptable indoor thermal environments.

Units: SI