condensing or non condensing

jonny88

i understand that condensing units drain of through a neutralizer what i dont understand is what happens in a non condensing unit.i thought if you burn gas you create carbon monoxide.where does it go in a non condensing unit.i just cant get my head around how it works even though im sure it is pretty obvious.thanks

Brad White

Condensing

What a condensing boiler produces as liquid waste is essentially water but with dissolved carbonic acid from the combustion process. There are also trace metals from the boiler and from minerals in the gas itself. Iron, zinc, chromium, things like that.



Natural gas, when burned as perfectly as possible, yields carbon dioxide and water vapor.



When burned imperfectly, carbon monoxide and nitrous compounds are produced. All combustion produces in reality some carbon monoxide, but efficient systems produce very little when operating properly.  Some aldehyde products are produced, partially from the ethyl mercaptan odorant mixed in with the gas. Cannot be helped.



The nitrous compounds are produced as a function of the air supplied for combustion.



All combustion needs from the air is oxygen, which at sea level comprises about 21 percent of air. 78 percent of air at sea level is nitrogen, going along for the ride and doing nothing for you. Too high a temperature and the nitrogen combines with excess oxygen to produce oxides of nitrogen (NOx) but nothing recreational, dammit.



So in a non-condensing boiler, what goes up the chimney tends to have higher CO (carbon monoxide), more nitrogen compounds, water vapor (not condensed!), carbon dioxide, some aldehyde compounds. But the water vapor, well vaporized and not condensing until it hits the dew point (we hope in the open air and not before), is the dominant difference.

jonny88

thanks brad

thanks for taking the time out to answer my question.