direct to your inboxMoney Saving Expert Martin Lewis has issued a warning to millions of Brits planning to turn their heating on today.Appearing on ITV's This Morning, the finance journalist discussed whether or not people should keep their heating on all day.He said: "They say it’s better to only put the heating on when you need it."You pay to pump energy in as and when is needed and to keep pumping it in constantly isn’t efficient."Using a timer's best, because your thermostat is designed to