VigIIPeaBurner wrote:Are you trying to move the heated air to the rooms with your current vents? Most ductwork systems pull cool tempered (return) room air to the heating source and push the heated air (supply) to the rooms. In planning to move an amount of air out of the conditioned room, there needs to be a way to return at least an equal CFM volume of cool air.
No, using my existing hot air system could seriously upset pressures in the duct and even possibly have the furnace over temp cut out or cycle due to altered duct pressures. Return is no issue, there is already VERY free return to the room with the stove. Return is as vital as supply but already accounted for.
VigIIPeaBurner wrote:I've only seen the high speed ducts associated with cooling where they move very cold air to the room. For heating applications, wouldn't the air have to be very hot to move the required BTUs to adequately heat the room? If you really need high speed ducts, wouldn't you be more successful and comfortable moving colder floor level air back to the conditioned stove room? The heat will flow to that area where the lower pressure is. Cool air is more dense than warm air and will settle to the lowest point so just help it along.
Small high velocity ducts are used for heat and AC. However they are generally driven by the furnace's air mover.
I used "I'll need high velocity fans". High velocity, small diameter ducts moves the same CFM of air as conventional sized ducts operated at low (conventional) pressure, thus no higher temperatures are required. I'm seeking room-room transfer which will reduce propane usage. I do not expect to be able to eliminate my furnace, the supply is just another warm room. I do set the coal thermostat higher than usual most of the time since the family room is seldom used. It cools rapidly via stairway if desired.
My free return is already in place, thus room-room warm air is desired. The returns to some rooms are via upcut doors, thus denser air and gravity already assist. I'm only in need of moving warm air to the desired rooms. I am not interested in using high transfer grills that would be needed for any convection benefit.