How to train your thermostats so you cut costs and keep cosy

Set thermostatic radiator valves correctly when temperatures plummet and you'll stay warm while dialling down heating bills

Ensure your room is at a comfortable temperature. File picture

Temperatures will plummet to lows of -5C this week as the cold spell continues to bite thanks to Arctic air and as a Status Yellow low-temperature and ice warning impacts Munster, Leinster, Connacht, Cavan and Monaghan, we're doing our best to stay warm as well as safe. Although we try to keep those heating bills under control, we don’t always completely understand the settings that trim those costs with wet central heating. 

One of the most powerful basic additions to even the most challenged system begging for an upgrade is a thermostatic radiator valve or TRV. But there is some confusion about what they actually do.