Dear James: The old-tinted film on my windows blocks heat, but the corners are becoming loose and cracking. How do I remove the old film and install new film myself? —Lana T. Dear Lana: Old, deteriorating, tinted window film is still effective at blocking heat and glare, but it can look really bad and impair your view outdoors. Newer window films have much less tint. They use a technology similar to low-emissivity replacement windows to block the heat during summer and save heat during winter. Removing the old deteriorating window film is the most difficult part of this project. Never try to install new window film directly over old film. The key to an effective removal of old window film is to soften the adhesive so the film and adhesive can be peeled and gently scraped off the window glass. Several of the major do-it-yourself window film companies offer liquid …