DI Filter is leaking or unable to tighten:
In the situation where there’s small leak on the DI filter cap, please check the following. Disconnect water supply, unscrew the DI filter cap (blue color) and make sure the black O-ring (one ring inside each cap) is properly seated in the threads and there’s no resin beads trapped inside that may be causing the leak. Also look for wrinkle in the o-ring and hairline crack on the blue cap. Add some silicon or Vaseline grease on the O-ring before putting it back. Most customers are able to solve the leaking issue after performing the steps. Please kindly perform these steps and advise us the outcome.