There is a ball, shut off gas valve right there skip, put your glasses on. And a uion below it, whats up with the swing joint??
What's you problem with the expansion tank and air bleeder?
True, you gotta drain most of the system to change the water reg but whatever. That only needs done after years of service and usually is done while other major service is being performed.
I do have iso valves on the main piping so you can change the pump or access the boiler without draining the rest of the system.........you don't see that very often.
I'm holding off on the answer as to whats really in the craft store. I mentioned it once long ago, one of my exciting stories about customers.
8 zones on a double 007??
i wqould love to see what the flow rates to each zone amount to. what happens when all 8 zones are calling in the dead of winter. low temperature water heading for the boiler!!