Navien Flow Sensor Tankless Water Heater

Works like a charm! Like so many others, my Navien heater stopped working and this little part was causing all the trouble.If this helps someone, I own a NR180A heater, and the part this replaced was # 30011024H, which is no longer available. This is part # 30010537A and looks exactly the same, and is of exactly the same dimensions. It was a plug and play replacement, no need (or space available) for packing nuts, or additional O-rings, or the $350 price tag I got quoted for this fix. All I needed was a screwdriver, a wrench and about 10 minutes. I ended up reusing the wire from the original part instead of the one that came with this.

Fixed our Navien 210CR, had no hot water on all fixures at low flow. Had to turn on full flow to get hot water.Works great now. Very easy to install.Always replace o'rings when replacing this part to prevent leaks and damage to control pc board.

The Flow sensor was easy to install and worked great for 10 months and now failed, giving error 038E on my Navient NR-240A.

It took about a month to arrive in Canada. This sensor looks has a better internal design than the original sensor on my 10 year old Navien CR-240A. Hope it can last longer.

We were experiencing intermittent cold water from our 9 year old Navien NR–240A tankless hot water heater. We even have the recirculation loop to keep hot water in the pipes every 30 minutes. In recent months, every time I went to do dishes at the kitchen sink, I would have to wait for an extremely long time to get hot water. Sometimes I would start with hot water and then it would run cold. If I turned on the shower too, I could force more demand on the water heater and get hot water sooner. I did some searching for answers on YouTube and found that these symptoms are textbook and common at about 9 years. This was a very easy DIY repair. Just a few simple tools, a Phillips screwdriver, channel-locks, wire cutters for zip ties, replacement zip ties. Just watch some guys demonstrating how it’s done. You have to close the right valves and have a bucket to drain water into. But you can do it. This part worked perfectly and now we have hot water again.