but you also need a proper power flush in pipe work mate
Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws
Reply to the thread, titled "Not all Rads getting hot" which is posted in UK Plumbers Forums on Plumbers Forums.
We recommend City Plumbing Supplies, BES, and Plumbing Superstore for all plumbing supplies.