Hi, recently I had a new boiler fitted. I noticed that the original flow and return to the radiators is now reversed. The plumber did this by mistake. All the radiator thermostatic valves are bi-directional ones so maybe this isn't a problem. However I'm concerned that there may be other issues. For instance, would this reduce the efficiency of the system, or is the reversed flow of water likely to unsettle any 'gunge' and cause problems that way? Then again if I got the plumber to correct the flow and return would the system then need another flushing, what with water now flowing in a different direction?As you can see I could do with some answers! Any help would be much appreciated.PS I have also noticed that the Magnaclean unit has been fitted directly after the flow from the boiler and though I believe this is adequate it's not best practice and could have easily been fitted after the last radiator. Could this and the problem above suggest I didn't employ the best plumber on the block or maybe he was just having a bad day?