I am installing a fireplace insert and intend to use it as my primary heat source. I am now concerned that my radiator pipes will freeze because hot water is no longer circulating through them. My furnace also provides my home with DHW, so the furnace is always hot. My question is, does the circulator on my furnace operate anytime the furnace fires, or only when there is a call for heat from the thermostat? I need to find a way to run the circulator occasionally, but it would not be necessary if it is already running each time I take a shower. Thanks for any answers you can provide.

Do you have a indriect water tank hooked to the boiler or is there a inturnal heat chamber. Inless you have a huge gas log set I dought it will heat your intire house when it get really cold.

Thanks for your response. It has an internal chamber that I understand is a coil. The chamber is always hot.