If you are experiencing air leaks through your aluminum windows (and window replacement is not an option); there are other ways to mitigate air flow, maintain your current window, and keep the interior space at a more pleasant temperature.
Replacing the glass, the glazing seals, and the weatherstripping/gaskets at the operable units can reduce heat loss going out and cold air coming in the windows. Also, many aluminum window systems are interior glazed, which means the glass replacement can be done from inside the building. Certain types of glass, including tinted and low-E coated, in conjunction with gas-filled insulated glass units (IGUs), will increase the overall insulating value of the glass and window. Applying glazing tape and an interior cap seal will prevent cold air from leaking into the building around the glass unit. It doesn’t matter whether your window incorporates bulb, brush, pile, or vinyl weatherstripping. If it is in poor condition or missing, installing new weatherstripping will help keep the cold out.