This problem typically starts with an ERROR 001, ERROR 038, or ERROR 039, but your Navien could show a number of other errors caused by the faulty flow sensor. We will discuss further below.
First thing, if you need hot water immediately, try unplugging the system wait 30 seconds, plug it back in. This resets your tankless and may give you hot water again for a quick shower or temporary use. Don’t forget though, this type of error typically will reappear again shortly.
Disclaimer
We recommend you call a certified technician to replace your flow sensor, you are liable for any damage you cause to yourself, your tankless, and it could void your Navien warranty. That being said we understand that homeowners are squeezed in every which way for every penny they have, this is a fairly easy replacement job and the parts are cheap as well.
Replacement Navien Flow Sensor
- NPE/S model tankless – Part # 30011534A (out of stock)
- NPE/A model tankless – Part # 30008571A
- All other models* – Part # 30010537A
If parts are unavailable above they may be available through The USA Amazon which always has a far better selection of parts.
- NPE/S model tankless – Part # 30011534A
- NPE/A model tankless – Part # 30008571A
- All other models* Part # 30010537A
*Replaces BH1406004F, 30002669A, 30004802C
CC
CC180
CC-180
CC-210
CC210
CC-240
CC240
NP
NP180
NP240
NP240A
NP-240
NP-240A
CR
CR180
CR-180
CR180A
CR-180A
CR210
CR-210
CR210A
CR-210A
CR240
CR240A
CR-240
CR-240A
NR
NR180
NR-180
NR180A
NR-180A
NR210
NR-210
NR210A
NR-210A
NR240
NR240A
NR-240
NR-240A
How To Replace The Flow Sensor
Additional Notes
There are a few things to mention here.
- Sometimes the flow sensor just needs to be cleaned up and reinstalled to correct the error. If you have heavy scale and calcium in your water a good cleaning may be all that is necessary.
- Occasionally something like an error 012 will display indicating a flame loss, this could be indirectly caused by the flow sensor. If your flow sensor is working intermittently the tankless could read no water flow cut the flame but then get flow from the flow sensor again. This situation could theoretically then throw a flame loss error.
- Clean the water inlet filter/s. If these get clogged or gummed up water flow will slow to a trickle and you might get a false negative flow sensor error.
October 17, 2022
My flow sensor is reading low (gpm display much lower than coming from the faucet) and so not heating the water enough. Replacing the flow sensor has not fixes this. Any ideas on a next step?
January 3, 2022
I replaced it but now it is leaking! Any thoughts on fixing that?
July 2, 2020
Some additional information on cleaning the flow sensor on my NR-210A- once you remove it to clean it, there is a spinning impeller wheel inside. Mine was corroded to the point that it couldn’t spin. No signal was being transmitted so the heater thought there was no flow.
Once I cleaned it with a pipe cleaner and blew into it I heard that magic spinning sound. I have ordered a new flow sensor but for now I have hot water again!
April 9, 2020
Abril 9 del 2020.
Tengo 2 Navien model NPE- 240A.
He tenido problemas para que los tecnicos lo arreglen. por lo cual me gustaria que me recomendaran tecnicos calificados. la compania que me arregla los problemas de los NAVIEN es ALLGOOD. hoy 9 de abril del 2020, unos de los Navien mandan el Error # 439, a las 11:00:00 remplazaron la parte # 30008245A Nombre WATER ADJUST VALVE NPEA. me combraron $ 550 dolres, les pague y fui a mirar el NAVIEn y continuava con el mismo Error 439, Lo checaron nuevamente y me indicaron que ya estaba listo. fui a checarlo y estaba el mismo Error 439, regresaron para resolver el problema y me dijero que se iba a reparar solo ya que lo habian reseteado. pero paso el tiempo y no se arreglo el problema. el tecnico ya se retiro. me cobro los $ 550 dolares. y el NAVIEN 240a Sigue mal. por favor necesito un TECNICO CALIFICADO. LOS TECNICO QUE TIENEN LA COMPANIA ALLGOOOOD. NO SABEN REPARLOS. PERO SI SABEN COBRAR.
mi numero Celular es 770 841-8218