Came out for kitchen sink not draining. Sink was backing up when water was ran. Checked AAV to make sure it was working fine, no problem. Received approval to snake. Ran flex shaft and tub gun down the line multiple times. Could not clear line. Had to go get bigger mainline flex shaft and come back. Returned and put down tarping and large trashcan under cleanout in basement. Ran mainline flex shaft down drain and had LOTS of grease come out the cleanout and go down the line. Massive chunks of solid grease. We restored flow to the drain and camera’d to ensure no issues. Found that the piping servicing the kitchen sink was replaced in 2012. 20’ run of 3” pipe is completely flat. This allowed grease to build up over 20 years. Left quote to replace the piping. Recommended they treat the drain with a liquid drain cleaner periodically. No further issue at this time.
