Flue Gas Condensing Temperature - HVAC-Talk: Heating, Air ...
As I am now dealing with a job that has Lochinvar CHHN0990 non-condensing boilers that were condensing in the boiler as well as the flue, I've done a little search and found that natural gas flue gas condenses at 60*C, which equals 140*F. Coincidentally, that is the minimum allowable return water temperature to these boilers. Return water less than 140* is no longer a problem.
Read More