My hydronic heat system has one large loop around the basement perimeter from which two tees feed each radiator on the upper floors.
An HVAC friend of mine suggested that the one single large loop is the old way and the modern way is to have two loops (one supply and one return) in the basement, and that this new way is more efficient.
Perhaps this alternate way may provide more even temperature distribution? But how would you regulate water flow to each radiator in an even manner? The single loop way I'm familiar with is to use venturi tees to encourage circulation through its respective radiator. What's typically installed for similar type systems these days?
Anyone have an opinion to offer?
-Anthony