We have a Nortiz tankless water heater model N-069M. It takes a little while to get the hot water going. After being in the shower for about 10 minutes, it suddenly goes ice cold. And I mean REALLY cold. It takes a good full 3-5 minutes before the hot water gradually comes back. No other appliances running and no one else using water in the house.
I noticed some corrosion at the couplings near the bottom of the tank. I was also wondering about the flue? Does this tankless water heater appear to be installed properly. (Side note - will be posting this under a different topic, but also getting electric shocks from all water faucets in the house. Not when touching the faucet itself, but when touching the water. I know this is an electrical issue, but was wondering if this might be a grounding problem related to the tankless water heater. Electric shocks also felt when turning on lights, TV, computer, etc. Not all the time, but a lot of the time.)
Here's the photos. Would love opinions. Thanks!