I actually had this same problem and I can almost bet it is a small animal (rat, squirrel, oppossum, something like that) has gotten into your walls and died. Have you put out any poison or had a...
It has a monitor heater in it now (we haven't moved in yet) it is in the living room, and dosen't warm the entire house, with kids we need to keep the house reasonably warm. Thanks for responding
My husband and I are buying a older home that is around 1,000 sq. ft. with 6 rooms to heat. With the cost of fuel so high we are thinking of taking out the monitor heat and replaceing it with...