Navien CR210A tankless error codes
I need some advice from someone with experience with Navien tankless water heaters.
Unit was working flawlessly, then hot water starts dying. It gives me an error code 38, and code 12.00. The 38 means abnormal circ pump error. What does the 12.00 mean?
The troubleshooting guide tells you to: 1) Check the cold water supply -- checked & cleaned out the cold water inlet filter, 2) Check the circ pump & 3) Check the water flow sensor.
So do I replace the water flow sensor or the circ pump? Anyway to troubleshoot this?