Navien CH240 drawing intake air from basement?

Ross_24

Just visited a new client of ours to take a look at their new heating system install. They have a Navien CH240 that is drawing intake air from the basement, instead of the usual outside air intake.



The manufacturer does include an option for non-direct venting, although it seems insane unless absolutely necessary (of course, in this case it's not necessary at all). In this case I believe the old dusty basement would quickly void the warranty.



Anyone else seeing this?

Rich_49

Besides

the possibility that if the house is tight where will the unit gets it's makeup air from then after inside air is exhausted ?  Not a good install in my opinion .