Recently I replaced my wood-burning heater with a split-system heat pump with a variable speed blower. Formerly the airflow direction was UP and through ducts in the attic. With the new system I had the contactor reverse the airflow, so that it's now DOWN and through ducts that were formerly used for return air. These ducts are embedded I the concrete slab. Problem: the air temperature exiting the new supply resisters is never warm enough, even when the auxiliary heater (electric resistance) is running. I fear that the concrete is absorbing too much heat. In fact, there are places in the house where the floor is noticeably warmer than most. Does his sound correct? If so, is there an insulation product that I can install in the ducts (round PVC)?
- posted
17 years ago