INFLUENCE OF NEGATIVE TEMPERATURES ON THE THERMAL CHARACTERISTICS OF PVC WINDOWS

Abstract

The experimental studies of thermal characteristics of PVC windows at negative temperatures of the outside air are performed. The experimental studies results are compared with the requirements of regulatory documents and existing calculation methods of infiltration heat loss through the windows. The laboratory tests show, that under the influence of the temperature difference of the external and internal air (in winter) window profiles get large deformation. The temperature deformation of PVC profiles and window gaskets elasticity degradation lead to a violation of the window thermal characteristics. The effect is to increase the windows air permeability and reduce the temperature on the inner surfaces of their profile elements. This leads to an increase in infiltration heat loss through the windows and violation of the normal microclimate parameters in the room. The established effect of reducing the PVC windows thermal characteristics at negative outside air temperatures is not taken into account by the existing calculation methods.