Patent ID: 8201553

Claim:
A solar hot water system, comprising: an ambient temperature sensor; a controller; a valve, including: a body having a first port, a second port and a third port, and a member, within the valve body, controllable to open a first fluid communication path between the first port and the second port and a second fluid communication path between the second port and the third port, the first fluid communication path closing before the second fluid communication path opens, and vice versa; a water storage tank having an inlet and an outlet; and at least a first solar panel having an inlet in fluid communication with the water storage tank outlet and an outlet in fluid communication with the water storage tank inlet, wherein, when the temperature sensor indicates to the controller that the ambient temperature is above a predetermined level, the controller controls the valve to direct flow from the first valve port to the second valve port, thereby directing water to flow from the water storage tank outlet to the solar panel inlet and from the solar panel outlet to the water storage tank inlet, and when the temperature sensor indicates to the controller that the ambient temperature is below a predetermined level, the controller controls the valve to direct flow from the second valve port to the third valve port, thereby directing water to drain from the solar panel inlet to atmosphere.