Report "Typical problem having to do with the Explorer grq15 refrigerator. It never really did get cold, but always seemed to keep food cold. Now the lower box isn't getting much lower than 56*. I cleaned the flue, checked the burner and the gas pressure. Can I apply moderate heat to the small tank on the rear and gently tap it with a rubber hammer to possibly loosen up the ammonia? This refer. sits all winter in a snow covered cabin. Maybe it's time to burp it"