Modeling of central domestic water heater for buildings

A theoretical study has been carried out on the transient behavior of central domestic water heater. The heater is mathematically modeled and governing equations are solved by Runge–Kutta method. Variation of performance parameters such as duration of water heating until temperature of water in heater tank reaches up to 60 °C which is the design parameter for the heater and temperature of water in tank during warm water consumption period versus mass flow rate of fluid flowing through the heater coil are studied to determine an optimum range for the mass flow rate that specifies the circulation pump size.