Called out to complete sold work. Began work by shutting off the water to the home and draining the system. Did a tankless flush on the navien tankless heater in the garage. Also installed a new check valve and expansion tank for the navien tankless because it did not have one before and per code it requires one. Installed crossover tee under kitchen sink, and set navien settings to enable recirculation on the system, once all work was complete test at all work for leaks and functionality. No leaks, and everything is functioning properly. Thank you for trusting TE certified with all your plumbing needs.