I have a 4 zone water based heating system. One S-25 BF Cast Iron In-Line Pump, 1/12 hp heat pump for all 4 zones. The spring circulator breaks every year. It just broken again eventhough the assembly does not require any lubrication on S-25 BF. Before this model I had S-25 which required lubrication and I could see that on those old pumps lubricant oil was causing issue so I bought this one. Now it broke again.
Why is spring ciculator breaking every year?
Is there heatpump w/o circualtor that I can use in place of S-25 BF. Do I need a more powerful pump?