1. What Is Flow Temperature? Understanding Flow Temperature: The Key to Efficient Heating When it comes to heating your home, most people focus on the thermostat and overlook a crucial factor: your boiler's flow temperature. But what exactly is flow temperature, and why is it so important? Flow temperature refers to the temperature at which your combi boiler heats the water before it circulates through your radiators. Many homeowners might not realise that their boiler is likely set at a high...