Joanna Davis14:04, Jul 03 2021 Unsplash A credit card works too, at a pinch. I had to de-ice the car’s windscreen this morning. Our elderly dog refuses to go for a walk. The car’s thermometer read the outside temperature at 2 degrees as I dropped my son at his football game. Yes, it’s cold outside. This set of circumstances could be considered entirely predictable, considering it’s mid-winter, but it prompts this question from “Puzzled of Island Bay”: “As I work from home in the cold: why is it that fan heaters blast heat but the minute you turn it off the heat disappears? But the heat from an oil column heater seems to last?”