I was called to a home with a Navien boiler that was not heating the home. I found the system was air locked. I cleaned the inlet water filter and bled the heat exchanger. The boiler was running when I left. I made recommendations to install a couple of new parts and will be back next week to install the parts to make sure the system stays running. Thank you, Ruthan, for calling Perrysburg Plumbing Heating and Air Conditioning LLC.