Dahveed
New Member
For months we have had this intermittent hot water problem with our Navien NPE-240A. Water would be hot and then gradually cool down to 104-110 degrees, depending on the faucet. It made for very quick showers ;-) Nothing online in the trouble shooting blogs seem to point to a specific problem but staying true to the manuals, I cleaned all the filters and ran Haymaker through the system for 90 minutes to no avail. My plumber Dave showed up and he replaced the cold water flow sensor (30011534A), the Water Adjustment Valve (30011532A), and most of the thermistors. Still no change. Pressure was always fine at any faucet so water flow didn't seem to be an issue but as Dave the plumber was following the cold water lines within the Navien housing he noticed in the line out of the Recirculation pump what looked like a valve. Looking it up in the manual determined it to be a check valve, which prevents cold water from entering the hot water side. Mine was broke and was allowing cold water to enter the hot water stream and cool
it down. While I await a new part, my plumber removed the internal components, changed re-circ to internal Pic 2) and reset the dip switch to recirc internal and it's working perfectly
it down. While I await a new part, my plumber removed the internal components, changed re-circ to internal Pic 2) and reset the dip switch to recirc internal and it's working perfectly
