Have you run plenty of water through the DI can,when you first setup you will need to run the water through for 5-10mins to get the reading down to 000 with new resin.Saying that you say you`ve cleaned your window`s with it so if it`s new sounds a bit strange,is the meter calibrated and are you taking a reading from the water in a clean container,001 is absolutley fine but it`s weird if it`s a new system with new resin i reckon it`s only the meter,try another one.