PROTECTIVE DEVICE FOR SOLAR HOT WATER SYSTEMS

摘要

A temperature sensitive protective device (8) for an electrically boosted solar water heater, characterised by a first and a second automatically resetting thermostat (T1, T2), a resilient means (16), an actuator (30), a first and second switch means (20, 22) and a fusible resistor (24). The fusible resistor (24) holds the resilient means (16) in a compressed state. If the first thermostat (T1) fails, resulting in power continually supplied to the electric booster and the second thermostat (T2) changes state, the first switch means (20) will change state, fusing and disintegrating the fusible resistor (24). The resilient means (16), thereby released, urges the actuator (30) to change the state of the second switch means (22), removing power to the electric booster until the fusible resistor (24) is replaced and the resilient means (16) is manually reset.