Richard Wick
New Member
Hello, hoping people here can help with a loud Navien 240A revving sound.
Replaced two tanks that had a continuous circulation pump on dedicated copper recirculation line with a new Navien 240A tankless. Originally set to EXTERNAL recirculation using the pre-exisiting dedicated recirculation line and unfortunately, we had a water hammer effect in our walls. This only happened with the recirculation phase of the operation and was thought to be due to variation in pressure and temperature in the recirculation line.
To remedy this, we worked with the plumber and navien sales rep to install a 6-gallan electric tank that supplies the dedicated recirculation line (DHW goes out from navien into the 6-gallon tank, hot water goes from the tank up to the house. Recirculation line comes back to the tank using a dedicated TACO pump). We now have it set to INTERNAL recirculation per the rep's recommendation (Switch in left lower portion of the unit set to INTERNAL, and dip switche set to 1-ON, 2-OFF, 3-OFF)
About two weeks after this set up was done (not immediately after the extra tank install) we get a very loud noise from the inducer fan, AFTER the hot water is used and turned off (My understanding is this is at the time of the gas purge).Through trial and error, we have turned OFF recirculation completely (all DIP switches OFF) and we now get the loud "revving" sound when the unit kicks ON for a hot water pull from the house, but does NOT rev at the end(??).
It is very loud and heard one floor up from where the unit is installed. I will try to post a video shortly (I think it's saying the file size is too large): This video was taken while it was still in the INTERNAL recirculation setup.
Any help in understanding if this is a normal sound is appreciated. Honestly, it drives me nuts and I regret installing this Navien if this is thought to be a "normal" operational sound. Im wondering if its tied to the recirculation feature and/or a loose barring in the fan.
Replaced two tanks that had a continuous circulation pump on dedicated copper recirculation line with a new Navien 240A tankless. Originally set to EXTERNAL recirculation using the pre-exisiting dedicated recirculation line and unfortunately, we had a water hammer effect in our walls. This only happened with the recirculation phase of the operation and was thought to be due to variation in pressure and temperature in the recirculation line.
To remedy this, we worked with the plumber and navien sales rep to install a 6-gallan electric tank that supplies the dedicated recirculation line (DHW goes out from navien into the 6-gallon tank, hot water goes from the tank up to the house. Recirculation line comes back to the tank using a dedicated TACO pump). We now have it set to INTERNAL recirculation per the rep's recommendation (Switch in left lower portion of the unit set to INTERNAL, and dip switche set to 1-ON, 2-OFF, 3-OFF)
About two weeks after this set up was done (not immediately after the extra tank install) we get a very loud noise from the inducer fan, AFTER the hot water is used and turned off (My understanding is this is at the time of the gas purge).Through trial and error, we have turned OFF recirculation completely (all DIP switches OFF) and we now get the loud "revving" sound when the unit kicks ON for a hot water pull from the house, but does NOT rev at the end(??).
It is very loud and heard one floor up from where the unit is installed. I will try to post a video shortly (I think it's saying the file size is too large): This video was taken while it was still in the INTERNAL recirculation setup.
Any help in understanding if this is a normal sound is appreciated. Honestly, it drives me nuts and I regret installing this Navien if this is thought to be a "normal" operational sound. Im wondering if its tied to the recirculation feature and/or a loose barring in the fan.
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