COMMON CAUSES OF A COLD RADIATOR & HOW TO FIX THEM With this cold weather here to stay, here’s a number of different reasons why your radiator might not be heating up properly (or is burning hot!), and the DIY solutions to get your house warm this autumn/winter. If one (or a few) radiators aren’t heating up (or are too hot) it’s usually one of these sneaky culprits: 1️⃣ Stuck TRV pin – wiggle it gently to free it up. 2️⃣ Needs bleeding – trapped air stops hot water circulating 3️⃣ Lockshield ope