See, what happens is throughout the summer when you turn your radiators off by the TRV (Thermostatic Radiator Valve), the pin inside the valve body tends to seize closed, in most cases this can be sorted with just a little DIY! Just follow the steps in the video and this could potentially save you $100’s in call-out fee’s to engineers/conpanies! Thank me later and keep an eye on my upcoming posts of more DIY tips and tricks from a highly experienced Plumbing and Heating Engineer