a). Working with hot water pipes, and central heating pipework you should always ensure that the joint stays dry when the pipe gets hot as it is a usual occurence for it to be dry when the water cools down, but leak when the water heats up.b). Removing paint from copper pipes can be quite a difficult and time consuming job but is necessary if you want leak free pipes. In order to do this, open a set of pump pliers and gently grip the pipe. Begin to turn the pliers back and forth and this usually dislodge the paint and cause it to flake away.c). Moving a block in pipework can be awkward, however, you could use a water vacuum cleaner to blow through. Make sure that all the overflows are covered over and plugholes are fully shut off. Should the pipe be solvent welded, this way can work well, but its not the best to use for push-fit pipes as it may blow the joints off the pipe ends. It does make a mess but is very effective. Wandsworth Plumbers can unblock pipework.d). It is common that you will find a plastic fitting, that has a plastic thread and is fitted to a copper pipe with a brass nut. The nut can sometimes cut through the plastic thread very easily which can cause a leak. (A Wandsworth Plumber can use plastic pipework). To guarantee this does not happen, always tighten the nut by hand, being quite gentle. If the nut is hard to turn it is probably ‘threading’ the joint which means that the brass is cutting its own way through the plastic rather than following the thread. Unscrew the nut, and make sure that the pipe is going straight into the fitting and is not at a funny angle, check it for damage and start again. Try and have the fitting loose itself so that you can be sure that the pipe and fitting are lined up perfectly, you can’t do this this with taps but is the best way with ball valves.