Flow control in solar heating panel - uses sensors, insulated from ambient temp., to measure temp. difference between water inlet and outlet

摘要

The flow of water through a solar heating panel (1) is controlled by sensors on the inlet (6) and outlets (5) pipes. A temp. difference over the preset value energises a pump (3), causing water to flow into the heat storage tank (2). When the water in the panel has transferred its heat and cooled sufficiently the pump stops. The sensors are insulated from the ambient temp., only detecting the heat in the pipes, and the control unit (4) can be programmed to ensure a gradual start-up of the pump. To prevent overheating, the lower temp. sensor stops the pump if its water temp. becomes too high.