A direct digital control algorithm for control of dry bulb temperature in a single environmental space is developed. The algorithm is based on a bilinear mathematical model, developed in the paper, of the response of the space dry bulb temperature and moisture content. The algorithm is somewhat unique in that it includes feedback and feedforward terms in a manner respecting the bilinear nature of the controlled process and as well, minimizes a practical performance index. The discrete time form of the algorithm is presented and simulation results given.