Pete Carlone
New Member
Greetings. New to this forum but I saw other Navien posts on here so thought I could get some help.
Here's the story:
Just moved into a house and the previous homeowners had a Navien NPE 240A installed. I wanted to get it checked out (so that someone could explain to me how it worked overall) and also descaled since I wasn't sure how recently the previous owners had done that. When doing the initial inspection, we observed that it was running in recirc mode but without any recirc valves downstream at any faucet locations and without an external recirc pump (although I know the 240A model has internal and external recirc mode so an external pump is not required if it has recirc valves installed). I had them come and install recric valves (Navicirc brand) at multiple sink locations. So, we have 3 recirc valves at 3 downsteam sinks. In addition to installing the recirc valves at the downstream sinks, they installed a T connection and manual isolation valve from the domestic water supply (cold side) to the recirculation port (previously capped) on the 240A. The 2-way valve was set to INT (for internal recirculation mode) and the dipswitches were set to 1-On, 2-Off, 3-Off. No other settings in the R&D information menu were adjusted.
My question is about what the right settings are in the 240A for the 2-way valve and the dip switches knowing that I want recirculation and that I now have recirc valves installed (with no external pump). I'm confused by what they did on a couple of levels but they insisted that this is how they always set up the 240As and recirc valves.
My confusion stems from a couple of things:
1. I don't understand why there needs to be a connection to the external recirculaton port if it is running in internal reciruculation mode. I feel like that line should have remain capped. Why did they need to connect to this port if they kept the 2-way valve on the internal setting?
2. If you look at the Navicirc installation manual it shows a T-line connecting to the recirculation port (which is consistent with what they did), but, it also says to set the 2-way valve to external, and to change the dip switches to 1-Off, 2-On, 3-Off. It also says to change a couple of settings in the R&D menu. Is there a reason why they didn't do these things too?
It seems to me that they should have installed the recirc valves and either left everything in internal recirculation mode (2-way and dip switches) with no connection to the recirc port OR made the connection to the recirc port like they did but also changed the 2-way and dip switches to external mode. Am I off base in thinking it should be one or the other? How would you normally set it up? Will it work as currently configured?
This was all done in the last 12-hours so I haven't had a chance to test the system performance overall, but, I have a feeling in the pit of my stomach that things are set up quite right. I'm a nuclear engineer by trade so I understand valves, fluid flow etc. I don't however have any specific knowledge of tankless water heaters and I typically leave that to the experts.
What should I do?
Here's the story:
Just moved into a house and the previous homeowners had a Navien NPE 240A installed. I wanted to get it checked out (so that someone could explain to me how it worked overall) and also descaled since I wasn't sure how recently the previous owners had done that. When doing the initial inspection, we observed that it was running in recirc mode but without any recirc valves downstream at any faucet locations and without an external recirc pump (although I know the 240A model has internal and external recirc mode so an external pump is not required if it has recirc valves installed). I had them come and install recric valves (Navicirc brand) at multiple sink locations. So, we have 3 recirc valves at 3 downsteam sinks. In addition to installing the recirc valves at the downstream sinks, they installed a T connection and manual isolation valve from the domestic water supply (cold side) to the recirculation port (previously capped) on the 240A. The 2-way valve was set to INT (for internal recirculation mode) and the dipswitches were set to 1-On, 2-Off, 3-Off. No other settings in the R&D information menu were adjusted.
My question is about what the right settings are in the 240A for the 2-way valve and the dip switches knowing that I want recirculation and that I now have recirc valves installed (with no external pump). I'm confused by what they did on a couple of levels but they insisted that this is how they always set up the 240As and recirc valves.
My confusion stems from a couple of things:
1. I don't understand why there needs to be a connection to the external recirculaton port if it is running in internal reciruculation mode. I feel like that line should have remain capped. Why did they need to connect to this port if they kept the 2-way valve on the internal setting?
2. If you look at the Navicirc installation manual it shows a T-line connecting to the recirculation port (which is consistent with what they did), but, it also says to set the 2-way valve to external, and to change the dip switches to 1-Off, 2-On, 3-Off. It also says to change a couple of settings in the R&D menu. Is there a reason why they didn't do these things too?
It seems to me that they should have installed the recirc valves and either left everything in internal recirculation mode (2-way and dip switches) with no connection to the recirc port OR made the connection to the recirc port like they did but also changed the 2-way and dip switches to external mode. Am I off base in thinking it should be one or the other? How would you normally set it up? Will it work as currently configured?
This was all done in the last 12-hours so I haven't had a chance to test the system performance overall, but, I have a feeling in the pit of my stomach that things are set up quite right. I'm a nuclear engineer by trade so I understand valves, fluid flow etc. I don't however have any specific knowledge of tankless water heaters and I typically leave that to the experts.
What should I do?