Does my air conditioner unit double up as a heater in the winter? Jessica 24 November 2021 13:37 Updated Most portable air conditioning units do not double up as a heater, but we do sell a 12,000 BTU 4-in-1 Portable Air Conditioner & Heater which can be used all year round. Related articles Will my air conditioner unit cool my whole house? Can I use a portable air conditioner in a room without a window? What size is the window kit? How often do I need to drain the water tank? What size air conditioner shall I get?