Tankless w/external circulator

[Daniel Collick]

Is there a gas fired condensing tankless unit, with top mounted water connections, that works well with an external circulation pump?
I like the top connections that are available in one of the Noritz lines, but none of them have a built in circulator.
I know Noritz is one of several manufacturers that have a model with a built in circulator, but I can’t a model with a built in circulator that has top water connections.
Anyone doing this without using a small storage/buffer tank?

 

[GReynolds929]

Noritz is the only manufacturer I know of that makes top connection models with their EZ series. They do not have a built in pump, but you can use an external pump with them. The purpose of a buffer tank is to eliminate the cold water sandwich effect, and is optional on the noritz EZ series when using an external recirculation pump. So you don't have to use a buffer tank unless cold water sandwich is an issue.

 

[Sponsor]

 

[Daniel Collick]

I also didn’t know that Noritz makes a circ pump, RCPK-EXT, to be paired with the EZ line. Hope this info helps anyone else looking.

 

[Breplum]

I wouldn't bother with the add on. Just change piping and go with a condensing Noritz or better IMHO Navien. 95%+ efficiency and