How long do HVAC units last?
Hereof, how long does the HVAC system last?
Heating, Ventilation, and Air Conditioning (HVAC) Furnaces on average last 15-20 years, heat pumps 16 years, and air conditioning units 10-15 years.
Keeping this in view, how much does it cost to replace HVAC system?
The average cost to replace an HVAC system is $4,820 to $9,350, which includes the combination of a new central air conditioner unit and a new gas furnace. Installation of a new HVAC system with ductwork costs between $6,820 and $12,350 in total.
If the AC unit were a removable window unit, then you could use 5 years, since the window unit could be considered an appliance. But if the "AC/furnace" is part of the structure and is what is called "central heat and air", then the unit is part of the structure itself, and must be depreciated over 27.5 years.