DIRT-PROOF WATER LEVEL SENSING DEVICE AND SOLAR WATER HEATER USING SAME

摘要

A dirt-proof water level sensing device for a solar water heater belonging to the technical field of water heaters. The device comprises a water tank (14) and at least two water level electrodes (7, 9). The water tank (14) is provided with a bypass pipe (15). At least one water level electrode (7, 9) is electrically connected to the water tank (14) directly or indirectly, and insulated from the other water level electrode (7, 9). The other water level electrode (7, 9) is electrically connected to the bypass pipe (15) at a height equal to a predetermined water level of the water tank (14). As the water level electrode (7, 9) is in a state where it is connected conductively with a circulation pipe of metallic material and an inner liner of a heat collector, correspondingly increasing the surface area of the water level electrodes (7, 9) themselves, failures of the probe due to fouling are greatly reduced, and the existing pipes are utilised rationally as constituent parts of the liquid level sensor, and therefore, a significant advantage in costs is achieved. Also disclosed is a solar water heater using the device.