Luis is one special man. When he opened the vent below my fairly new air handler he found a leak, and a defect in the installation. He was all ready to repair it when we decided that this could cause a problem with the warranty. So he treated the mold and took video explaining what he found. He cleaned my vent and spent a lot of time dealing with it all. I give him 5 stars because he was very kind and went above the call of duty. Thank you Luis!