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Low limit not turning on boiler
I have old oil furnace with tank-less coil for hot water. HWBB throughout the house. Recently the call for hot water from using hot water is no longer triggering the furnace to fire up. The call for heat works fine as long as the temp does not go below the low limit set point. I've found a work-around when we need to shower, and that is to kick my thermostat up a couple degrees, which quickly causes the furnace to fire up, and then we enjoy our scorching hot water in the shower. This isn't so bad when its really cold out, but as it is getting warmer, I won't need the heat as much. Why won't the drop in water temp trigger the furnace all of a sudden?