Tankless water heater flush needs performed as apart of our HCC maintenance plan. We also need to open up kitchen ceiling to look into leak coming from upstairs shower. Multi tool cutter recommended. Out today 12/5/23 Trevor J. Return trip to flush the tankless water heater. On previous trip, pump did not work. Returned with new pump and performed tankless flush. Upon inspection of the upstairs shower, I removed the existing cover from the drain. I discovered this is a compression style shower drain. Someone caulked the grommet. Removed caulking from drain and the bonnet nut. Found that the grommet was installed upside down and the bonnet nut was loose. Pipe was moving freely. Sealed grommet, reinstalled bonnet nut and secured drain. Ran water to test for leaks. Job Status: Complete.