tclederman, I think the one your are referring to was called a DELUXE heater. I have one that is NOS never been installed in orginial box labeled "Deluxe Heater", made by Harrison. This heater can be used as a fresh air, recirculating or anywhere in between.
wodniw5, the heaters will fit a COE or 3100, recirculating, fresh air or deluxe.
