Hi guys, im new to this but here goes, i recently drained my central heating system to adjust some pipework in the bathroom, no probs, once i refilled the system i found that the heating worked fine, but the cylinder would not heat up, 
, the tanks r both full and working ok, and the boiler seems 2 b firing as and wen its asked 2 ,theres no venting stem in the airing cupboard, so i cracked the top and bottom nuts that enter the side of the cylinder and their both dripping water, i also poked wire down the vent pipe, and it seems pretty clear, i tracked most of the 2 inch pipes back 2 the boiler and their not getting warm at all , ive added sludge remover, 3 days ago , but still nothing, no motorised valves as far i can see, so im totally baffled, plz help guys, 
, the tanks r both full and working ok, and the boiler seems 2 b firing as and wen its asked 2 ,theres no venting stem in the airing cupboard, so i cracked the top and bottom nuts that enter the side of the cylinder and their both dripping water, i also poked wire down the vent pipe, and it seems pretty clear, i tracked most of the 2 inch pipes back 2 the boiler and their not getting warm at all , ive added sludge remover, 3 days ago , but still nothing, no motorised valves as far i can see, so im totally baffled, plz help guys, 
