Near-boiler piping preferences?

Jim Erhardt_3

In regards to hot-water systems, do you have a preferred way to configure near-boiler supply piping? Now I understand that this is a very broad question and that there are many variations in system design that will determine some of the finer details. But for example;

1. In the case of series loop baseboard, fan coils, etc., do you prefer to use a single "purge station" arrangement on the boiler supply as opposed to individual purge valves on the return of each zone?

2. Do you prefer to pipe the PRV into the system with the expansion tank?

3. Do you prefer to pipe the expansion tank (and perhaps the PRV) into a bottom tapping of an air separator?

4. If you answered "yes" to the questions above, would you be interested in products that simplify such piping preferences, taking up less room and providing greater function?

Your input is very much appreciated!