No flow at all from tankless

[2002sheds]

Hi,
I am a bit sheepish in even asking this, but immediately after cleaning the inlet filter on our Noritz tankless heater I am experiencing zero water flow from the outlet side, even when tripping the pressure relief valve.

The shutoff valves are in the correct positions 9I have verified this several times now), and water

 

[Terry]

The pressure relief valve does nothing for flow.

 

[Sponsor]

 

[Reach4]

I am a bit sheepish in even asking this, but immediately after cleaning the inlet filter on our Noritz tankless heater I am experiencing zero water flow from the outlet side, even when tripping the pressure relief valve.

Maybe clean the filter again?

 

[2002sheds]

Hi All,
Well, stupid is as stupid does... I did go back to the heater in the last few minutes, and got to the control panel, which is under some stairs. Somehow, when I was under there earlier, I must've missed the flashing error code. Since I did not have even my phone with me to check what the code was, I went for the tried and true method of turning off the panel and turning it back on. Immediate success. There obviously is a valve inside the unit that was closed, and it opened once the heater was reset... Doh !

I'm posting this here in case someone else runs into the same situation.


Thanks,
David

 

[2002sheds]

Hi Reach,
Thanks for your response! It must've come through while I was posting my update. It turns out that the error was my stupidity (once again)... see above


Thanks,
David

 

[2002sheds]

The pressure relief valve does nothing for flow.

Hi Terry,
Thanks for the reply. Without having looked at the control panel, other plumbers have used the pressure relief valve instead of going into the house and opening a tap. When they would trip the pressure relief valve the unit would fire as the water rushed out.

I had already opened the hot water taps, but was trying to see if that method would rule out any sort of air lock or other issue in the plumbing downstream from the heater. My mistake was in assuming that the heater was more simple than it is — that water flow was completely (and only) affected by turning on the tap, instead of the reality, which is that the unit itself also has to be not in “error code mode” but on and in normal “ready” mode.

I was too lazy to crawl under the stairs to where the control panel is, and kept looking for solutions elsewhere, when I simply had to reset the control.

Thanks,
David