Abstract: An electric radiant heating system for heating building interior living and working space. The system comprises an electric resistance heating cable embedded in a cementitious thermal mass for transferring thermal energy to the thermal mass when an electric current is applied to the cable. The system utilizes a wall-mountable line voltage thermostat control to detect the temperature of the surrounding air, compare it to a selectable reference temperature, and perform a number of functions automatically depending on the results of the temperature comparison. High limit sensors, composed of bimetal strips, detect the temperature of the electric heating cable, sending a signal to the control means to interrupt power to the electric heating system when the electric resistance heating cable reaches a predetermined temperature. Cable-retaining hardware secures the electric resistance heating cable at regularly spaced intervals to the subfloor.

Abstract: A manifold which is useful in receiving a heated liquid such as warm water from a suitable source and for distributing that liquid to a plurality of floor heat exchangers and for receiving liquid from the heat exchangers and returning that liquid to the source. The manifold includes a plurality of separate manifold elements that can be stacked adjacent one another, each element having a first and second chamber. The first and second chambers of the elements together define first and second distribution vessels within the manifold. Each manifold element includes inlet and outlet ports communicating with the respective distribution vessels for carrying liquid to and from the heat exchangers. The manifold elements desirably are integrally formed from plastic or other material exhibiting a coefficient thermal conductivity of less than 1.0 kcal/M h .degree.C.