I will bet money the water machine is RO only possibly with UV but not DI. I have never seen one yet with DI. Have them test the TDS in front of you to see what it is. Around here its actually not bad at between 5 and 15 but thats still higher than I put in my tank and its inconsistent. Having my own RO/DI is the best investment I ever made, I know what my water quality is every time I make it, no guesswork.