How to Install & setup a Navien Tankless (series’s 1) without a dedicated recirculating line.

Does the NPE-A not normally let you use the recirculation pump if there is no dedicated recirc line? I thought if a sensor valve was installed at the farthest bathroom that it would still work.

Expansion tank up stream of a check valve does no good...

🤦‍♂️

How do you update the board and front panel on an older unit to get to p17?

Why os the expansion tank mounted horizontally...does the install manual not specify a verticle orientation?

You have a video about that auto descaller?