Remodeled House. Now Radiators Are Way Too Large

We installed this boiler and radiator system in 2017 when the owners purchased this house. Nothing had been done to the building since it was built; single glazed windows, no insulation.
I sized the radiators for 130F water temperature as I wanted the boiler to condense and they turned out very large. My supplier says I order larger radiators than anyone else. I suppose that’s a compliment.
Recently remodeled, the radiators are now way oversized and I can drop the heating curve even lower. It’s now set to 1.1 with zero offset and the radiators will only get warm, not hot. Safe for their new children and more savings on their utility bills.
Two btu per sq ft for degree difference for a slab
Comments
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Nice. Is the reason for the reduced heat lost because of their new insulation, windows, and air tightening? I suppose you do not have a new design water temp yet? But now much lower than 130F?
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@bjohnhy On a design day, 100°F water temperature.
@hot_rod This is the job I showed you when you were here. When you saw the boiler, you said, "You did this?" as though you couldn't believe I could do such nice work. I just cracked up.
8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour
Two btu per sq ft for degree difference for a slab5 -
Good problem to have. I noted that it appears you selected the 2 sided (runtals?) You may be able to replace with the single sided as a replacement using tge same valves and be just fine. Then just resale these doubles. Singles have a considerably lower output
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So what is the answer? Lower water temperature or slower water circulation? Theoretically either method can go too far.
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@tocker That’s not going to happen. The owners spent a lot of money to get the mass to drive efficiency. Changing radiators to smaller ones would mean increasing the heating curve; reduced efficiency.
The existing heating curve is approaching a radiant floor.8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour
Two btu per sq ft for degree difference for a slab2
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