Undersized Boiler? Make two Zones?

Hi Man,

Taking advice and experimenting with my second floor system, it has four shut offs on two main branches. I shut half the distribution and he was right, the boiler temp and supply ran up to a normal range (145F-155F) for the very first time in my history with this conversion. The supply remined low. Absolutely, the system works best on half the water. I could split the apartment into two zones. I don't want to spend for larger boilers. These are only two seasons old. Woud you try anything else?

As we have a history, You know my low boiler and radiatior temp problem. I finally have a workable premise for a possible solution !