Does a powerflush blow joints?

it can sometimes cause leaks to be exposed as the sludge and scale is removed it is unusual for it to burst pipework,24 years old ! and you have kept radiators ,was it a vented system before new boiler ? if so combi boiler is higher pressure so you may have same problem as power flush ie high pressure that may find weak spots in system,have you had magna clean installed ?,some boiler manufacturers will not gaurente boiler if you do not have power flush done before boiler is installed.

if you are worried about pressure use a magnaclean to remove a lot of the sludge ive used a low pressure filter hundreds of times and restored heating systems to the heat people had originally from when they first moved in.

Power flushing relies upon water and a good chemical additive passing around your heating system at high velocity, if it incurs a serious obstruction then we have a pressure build up. depending on where the obstruction is may cause a minor leak if by shear bad luck that choke point turns out to be a weak spot within your heating system. As long as you are confident you have made the right choice when selecting a company to undertake the power flush then just relax and let them carry out the work. I have undertaken several hundred power flushes of considerable variable aged heating systems both in commercial and domestic properties of over more years then I care to remember and I can count the number of minor leaks during this aggressive cleaning procedure on one hand, so please try not to worry