DIY Doctor UK DIY Forums

i have drained my central heating down to fix a leaky rad tap which i have done ,but i noticed whist draining the tank in the loft it only emptyed half way ,anyway ive done up all my bleed valves on the rads and let the ballcock off the string to fill the loft tank which it has done but it doesnt seem to be getting into the rads and boiler :cry: any ideas on this ,i noticed a lot of black sludge come out towards the end of draining and the loft tank is a bit dirty inside ,could i have a blockage somehere ?if so where would it be? help

hi simon sounds like a blockage this is normally between the tank and first tee piece try blowing down pipe in tank or feeding wire down if this doesn't clear then you have to cut and replace pipe to tee. if system and tank is emptied then you need a bucket and pipe cutter plus two push fit straight couplings. cut just above tee allowing room for fitting, clean pipe first all the best john