Is the water purified by MRO102-4 water purifier pure water?

Yes, according to your case should be RO machine, that is, the reverse osmosis principle of water, so it should be pure water, but the TDS value is about between 0-20, so it is not pure water in the full sense, in addition, you should know that your water machine with or without electricity, there is no wastewater, if electricity, there is wastewater, the ratio of good water and wastewater is about 1:3. Then you can conclude that your water machine for pure water machine, processing water for pure water