Watching the news last night the reports on the current cold affecting much of the USA showed several people demonstrating the extreme cold by throwing boiling water into air just to see it transformed into ice crystals immediately. I can see that in those circumstances a condensing boiler might have a few problems. I have seen icicles form on wire flue guards but never on the flue exit itself. Are we going to regret having condensing boilers when the next ice age comes?

Richard