A heating pro is asked to retrofit a pellet-fired boiler to an existing distribution system consisting of older cast iron radiators, iron piping and an oil-fired boiler. The system needs to draw heat from a thermal storage tank heated by the pellet-fired boiler, as well as an existing oil fired boiler. The original heating distribution system was designed to use 180° F supply water on a design day, but will now be retrofitted by outdoor reset control. This will allow the distribution system to operate at supply water temperatures as low as 100° F on mild days. A portion of the proposed piping layout is shown below. Can you identify several details that could be improved?