If you want to fix the gap between your air conditioner and window frame without spending much money or hiring professional assistance, here are a few low-cost solutions you can try:
Weatherstripping: Weatherstripping is an inexpensive and effective way to seal gaps around windows. Purchase adhesive-backed weatherstripping strips or foam tape from a hardware store. Apply the weatherstripping around the perimeter of the window frame, ensuring it forms a tight seal when the window is closed. This can help reduce air leakage and fill the gap.
Window Insulation Film: Window insulation film is a transparent plastic sheet that can be applied to the interior of windows. It helps reduce drafts and heat loss/gain. Purchase a window insulation kit from a hardware store and follow the instructions to install the film over the window. This can create a barrier that minimizes air leakage and covers the gap.
Foam Backer Rod: Foam backer rods are cylindrical foam strips used for filling gaps and cracks. Measure the width of the gap between your air conditioner and the window frame. Purchase a foam backer rod that matches or slightly exceeds the gap size. Insert the foam backer rod into the gap to fill it partially, and then use caulk or adhesive to secure it in place.
Rolled-Up Towels or Blankets: As a temporary solution, you can roll up towels or blankets and place them in the gap between the air conditioner and the window frame. This can help block the airflow and reduce air leakage. However, keep in mind that this method may not provide a tight seal and may not be as effective as other solutions.
Remember, these are temporary or DIY solutions, and for a more permanent fix, it's advisable to consult with professionals or consider professional installation or modifications to ensure proper sealing and insulation around your air conditioner.