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Zone valves on Weil McLain he2 boiler
We have a Weil McLain He2 boiler in my mothers home. The system has never worked right in spite of having several different plumbers including the initial installer working on it. One person suggested that the zones valves should be installed on the return side and not the supply side. That is the way I was taught so I thought it might be a possible fix. I have been looking for installation instructions for this unit, but cannot find anything relating to the zone valves. Does someone know or can they recommend proper installation?