One month after the new filter was installed, we discovered a water leak under the kitchen sink coming from the water filter. We had been unaware of the leak, since up until that time the water leak had been confined to the back of the shelf under the sink with the water finding its way to the spare bedroom on our lower level under the kitchen. We spoke with the owner of Tri-State Waterworks the next day. He claimed NO responsibility for the damage he said because he had not charged us labor for installing the replacement filter, which he said was just a courtesy. We challenged that, saying that if any compnay causes extensive damage in a customer's home, it would seem that they have to be responsible. He refused to look at the filter or the damage. We contacted a new water treatment service from Angie's List, and the owner with 24 years experience determined that the leak had come from a quick-disconnect fitting on the in-line filter and that the water line had not been pushed in past the second O-ring in the fitting to prevent leakage. He checked our water pressure, which not abnormally high, and concluded that the technician who installed the filter had not secured the water line past the second O-ring and must not have waited about 10 minutes after the water was turned back on to check that there was no leak. The damages incurred from the water leak amounted to over $7,000!