Navien - How should I set the 2-way valve if I want no recirculation?

[cpthk]

I have the Navien NPE-240A2. My question is on the 2-way valve. I was reading the installation manual. It described how to set up for internal recirculation and external recirculation. The 2-way valve should be set to either INT for internal recirculation and EXT for external recirculation. However, I cannot find any information about "no recirculation". How should I set the 2-way valve if I want no recirculation?

I tried calling Navien. Their support is not knowledgable. I was getting 3 different and conflicted answers from 3 different agents. One said the original setting (I can't remember which was the original), one said EXT, one said either is fine.

 

[John Gayewski]

It should be set for internal. When you turn on the Navien it will let you set no recirculation in the settings. Setting it to internal in the settings will give you more hot water quicker though. It decides when to circulate to keep the water warm.

 

[Sponsor]

 

[Bannerman]

The 240A and A2 models, include an internal buffer tank directly after the heat exchanger.

The small amount of water stored within the buffer tank, ensures hot water will be delivered more rapidly to fixtures, while also reducing the cold water sandwich effect which is common with tankless units that do not include a buffer tank.

Setting the valve and switches to internal circulation, will allow the water stored within the buffer tank, to circulate through the heat exchanger, thereby allowing the burner to periodically fire at a low rate, to maintain the temperature of the water within the buffer tank during periods when no hot water is utilized.

The diagram below, shows the internal recirculation path through the 'A' units. In the 'A2' units, the recirculation pump is located in an alternate location, similar to where the flow sensor is shown.