Originally posted by Noel Murdough
He says that he bought one of our gas boilers and connected it himself, he liked it a lot, it was good on gas, it was quiet, it always heated everything evenly, it cost less to heat last year with it than with the old boiler, but he had one question....

What's the 8" round hole in the top of the boiler for?

That would be the basement heat and humidification port. most people find that the exposed hydronic piping keeps their basement warm enough, so they connect the heat and humidification port to their chiminey.