Mode-Dependent Time Constants in Three Forms of Space Heating

The majority of published literature on system dynamics of space heating assumes that the constants in the exponential models for heating (active) and cooling (passive) are equal. Reports by Roots and his co-workers show that in one form of space heating the active and passive constants are not equal. This paper presents data from rigidly controlled experiments in an environmental test room under three forms of space heating. Active and passive time constants are reported for baseboard heating, ceiling cable heating, and forced air heating. Explanations are advanced for differences noted.