Ive restarted mine a couple of times for a different code until I could get a service tech to come out.

Who did the install? I’d try and find out and contact them as it’s likely still under warranty. I can recommend Tankless Concepts as they installed mine and were great.

New homeowners. Our newish Navien heater seemed to turn off overnight. Dh checked it and it was showing a flashing E10 error, which is a venting error. He hit the re-set button and it restarted, though is flashing the wrench icon. We will find a service provider who could come out and check it. DH thinks this could wait for next week (weekday), and if it was something serious it wouldn’t have restarted. My family had carbon monoxide poisoning when I was growing up so of course I went to panic mode. (We keep the windows cracked at all times and CO detectors built into our alarm system.) can anyone with one of these advise? Also happy to have a rec for service. I’ve seen Tankless Concepts referenced a couple times on a neighborhood blog.