Navien NR-240 No hot water after water main break

[Brianthill]

A company working in my neighborhood hit a hit and broke it yesterday. After the water came back on, my tankless water heater will no longer fire or give hot water. It is providing no error codes.

I have restarted the system many and cleaned the screen for the vent.

Could a water main break cause an issue like this? Any ideas on my next troubleshooting steps?

 

[Terry]

I can lose power, unplug and plug back in and my Navien will continue to work.

Here is the link to their support, or maybe someone here has some ideas.

Navien Product & Technical Support | Navien

Navien technical support offers coast to coast coverage with two world class support centers and live technicians providing the help you need, when you need it.

www.navieninc.com

 

[Sponsor]

 

[Brianthill]

Just realized my original post didn't make sense...it was a water line that was hit and we lost water for a few hours.

Is it possible there is just some crap in the flow sensor because of dirty water after they got it hooked back up?

 

[Fitter30]

The inlet screen could be block. Turn on a faucet or two look at the flow reading.

 

[Breplum]

Oh how I dislike those first-generation Navien NR series. If you don't have the service manual, it is a higher level pain.
The cold water inlet screen prevents crap in the flow sensor. The flow sensors do go bad.
Error code ?
If pump ran dry then that is something to check.