You run to a heat plate? Then you circulate from the plate to the boiler? Turn the circulator between the plate and the boiler off. Turn the thermostat to 50-55 deg. in the house. KEEP the OWB circulator going, should not freeze if still moving. No need to heat the OWB with the house unit. Some one told me you could shut the unit down and cut the water off above the circulator on the OWB, turn off the return (s), then drain the water from the lines so the water would be at least under ground. That would depend on what kind of piping you used and depth (frost line in your area). It depends on how cold it is up there. I think I could do either way now. Never had to shut it down yet so just food for thought.
LT...
LT...