Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Navien CH series vs NCB BTU rating

giantsean
giantsean Member Posts: 65
So to my earlier thread, Navien has agreed to warranty my now-defective CH-240, which is all but shooting fire out of the failed burner gasket (melting the wires in the process and more than likely causing all sorts of sensor drama).

Looks like the replacement will be an NCB-240 130H (though they said a 110 was another option). My concern is the space heating rating. I have two hydro air units good for about 95K BTUs supplied by this one boiler. It has always struggled to keep up on really cold days but I think that's more due to old house + lousy ductwork. The CH is rated for space heating at 199K BTU and the NCB about 120-130 I think. This seems like a big difference... should I expect any performance problems? Not that I'm complaining about a free replacement of an almost ten year old unit, but I don't want to downgrade either.

Thanks!