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ODR with conventional on off boiler
I don't understand how this could work. At least not in my case. As an example I tried lowering my high limit in small increments as temps outside rose. It seemed that below a certain point at almost any outdoor temp, all the boiler did was cycle on and of every 5 minutes. Yes I realize the ODR would control it better than what I was doing, but from what I saw leaving my limit above 155 was the only way to satisfy the therm without a lot of cycling. Maybe if there was a delta t circulator?