SIMULATED PERFORMANCE OF A COMBINED RADIANT FLOOR HEATING AND DOMESTIC HOT WATER SUPPLY SYSTEM UNDER DIFFERENT CONTROL STRATEGIES

A dynamic model of a combined radiant floor heating (RFH) and domestic hot water supply (DHWS) system is developed and validated by using measured data gathered from an experimental test facility. The validated model was used to study the dynamic responses of the system under different operating conditions. Optimal control and predictive control strategies were designed and simulated to study system performance and energy consumption. Results showed that the control strategy with the heating load prediction could save up to 12.7% energy. Also, the optimal control strategy with optimal set-points could save 8.6% energy input to the boiler and 42.9% pump energy consumption while maintaining the zone temperatures and DHWS temperatures close to their respective set-points.