Thermal responses to different residential environments in Harbin

In China, adding space heating in residential buildings is normally scheduled at the end of October each year, with heat supplied by district heating systems. This paper describes a field study of thermal comfort conducted in Harbin during the winter from 2009 to 2010 before and after the space heating is added. The aim is to study human responses to thermal conditions in the two periods in cold climates. 23 buildings in six communities were investigated. 199 occupants from 135 families and 174 occupants from 104 families participated in the two surveys during the two periods, respectively. The neutral air temperature before adding the space heating is 25.1 °C, while during the space heating, it is 20.4 °C. The clothing insulation is 0.77 clo and 0.88 clo, respectively. If they were 0.88 clo instead of 0.77 clo before adding the space heating, the neutral air temperature should be 21.1 °C. Before and during space heating, more than 80% felt acceptable at the air temperature range between 17.5–24.0 °C and 19.0–26.5 °C for the two periods. The residents’ physiological acclimation may contribute to the differences. The preferred temperature is within the range of 23.0–24.0 °C and 21.5–24.0 °C, respectively. The preferred humidity is 47.7% and 40.5% during the two surveys. People felt cold generally before heating, while they felt comfortable at the same temperature range during space heating period. People often felt dry during heating when the relative humidity is lower than 30%, while they felt comfortable at the same relative humidity before heating.