Termovar not allowing enough warm water through?

This is really interesing. Increasing the pump speed seems to have made a big difference. The problem has not reappeared. Our weather has gone from single digits to prolonged rain and tonight is moving back to single digits. Wish my part for the system monitor was in, bet the graph looks different. The house water may nose dive but I bet not for as long. Even when the house side of the circulators was showing 85 or 90, I could feel the surge of hot water when the house called for heat.

Do I understand that what I would call a loss of head, might be a cause? I guess in a more obsessive moment I should track the length, diameter and turns in my heating system. I have two types of radiators, upright and baseboard and those have to be worse than a couple of elbows. Not tonight

I was able to see the friendly people at BioHeat in Lyme yesterday. They said my motor switch should be in the middle position for speed. Also picked up two door seals for a summer project. When I got home I put it to the middle position.

In other news, the Xmas present heating system monitor is working flawlessly for the last couple of days. So I can play with that motor switch (high or mid) to see what goes on over any period of time. We have another heat wave coming so that will be a good test. I think I am going to get another temp probe for the stack temp, something that requires a rubber man to read, so I don't worry about it.

Think this just about does it for this thread. Thanks again.