How to adjust the water pressure: cut off the power firstly. Tear down the plastic cover, press "+" to Increase pressure (anticlockwise), press "‑" to reduce pressure (clockwise). For example (1.5‑2.2KG) technical explanation: when the water pressure is 1.5KG, the water pump will start automatically, and the 2.2KG pressure type water pump will stop working.
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