What's the matter with 18 1 displayed on the internal motherboard of gooday Health Water Station?

When the main board of the machine shows 18 1, it is also caused by water shortage of the machine. At this time, look at the internal left pressure gauge. If the data on the pressure gauge is 0 or less than 0. 1, the water inlet pressure is too low. If the data of the water pressure gauge is above 0.2, but the water shortage light is still on, it means that the first four filter elements are blocked and need to be replaced.