Propane gas (C3H8) enters a home furnace at 25oC, 1 atm, and burns completely with 15% excess dry air also entering at 25oC, 1 atm. The combustion products at 167 oC, 1 atm exit through the chimney after passing over the air heating coil. Air from the house enters the coil at 17oC, 1 atm, with a volumetric flow rate of 30m3 /min and heated air is discharged into the heating ducts at 50oC, 1 atm. There is no significant stray heat loss from the outside of the furnace, and kinetic and potential energy effects can be neglected. If propane gas costs $10 per 1000 m3 , determine the total seasonal fuel cost based on 2160 h of operation.