Our "Overwood" design is very similar to our "Larchmont" design in terms of the use of the 82% hot water boiler, primary/secondary piping, zoned pumping with Taco pumps, a Taco SR-EXP control system, a Taco 700-2 indoor/outdoor reset and the use of isolation valves on our system designed for service ("SDFS").
The added feature to the "Overwood" design is the addition of balancing valves to systems which were originally designed as gravity hot water heating systems.
Originally designed gravity hot water heating systems were often piped with 2-1/2 and 3" supply and return mains. They were also often piped "left and right" as opposed to floor by floor. In our "Overwood" design we install balancing valves on the 2 supply lines and 2 return lines so we can get an even flow of water to system radiation.