My last hot water question for a while, I promise...
In the new house we just bought, there is a partially finished attic with a radiator. The attic is essentially at 3rd floor level, so the radiator may be 25-30 ft above the basement boiler and circ pumps. I bled the radiator, and air came out of it very slowly---it probably took 30 min for it to fill up. Not surprisingly, in normal operation, no heat gets up there at all.
Is putting in a more powerful main circulator pump a possible solution? If I look at the curves on the Bell & Gossett's web page, some pumps move lots of water at zero head, but others can move more water at a given large head. The pump we have now is rated to go to zero gpm at 24 ft head, which fits with what I described above.
So if I get another pump that fits in the same space, and has some finite gpm at say 30ft head, will this work better? Or am I being naive and the water will merely take the path of least resistance through the lower radiators, and after a while the pipes will burst due to the higher pressure?
Is there another method to divert water up to the attic?
Many thanks,