Thanks to the help from you all in my other thread
, I'm getting ready to rebuild my boiler side to be "pumping away."
Before I do this, I want to try to solve another persistent problem where one rad doesn't receive any flow. I've attached a map that tries to show the layout and the smorgasbord of piping currently in place.
- This is a very old 2 pipe system with one circulator that has had rads added at different points over the years.
- Generally the house seemed to heat fine through the winter aside from the single rad identified as the problem rad which received no flow (when I tried disconnecting one of the pipes it looked like water was in the pipe but it wouldn't gush out or flow out even into the open air).
- This rad is fed by 1/2 pex Tee'd off a busy line
- The pex also runs up through the wall, into the ceiling joist and back down to feed the rad (I'm wondering if this loop is creating an air pocket).
- A couple of the basement rads are also fed by pex running through roof joists and back down into the rad, but they don't seem to have any issue receiving flow and heat.
- Only 2 of the newer copper lines have balancing (ball) valves; none of the steel have balancing valves. There are no zone valves. All balancing is done with the valves on the rads.
I have basement tenants so major pipe re-running is not possible, but boiler side work (balancing/zone valves, etc) is possible.