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Yes it can be done but unless the old boiler isn't working why would you. A one pipe system is only 70% efficient. So there would be no benifit. From memory only Vaillant allow thete boilers to be fitted to a one pipe system.Is it possible to fit a combi boiler to a single pipe heating system?
You could always fit a low loss header, or a plate heat exchanger and leave the old system as open vent but just the boiler as sealed, seen this done on a larger system in a care home
Where did you get that from; and how do you measure efficiency?A one pipe system is only 70% efficient.
Reply to the thread, titled "combi boiler on a single pipe system." which is posted in Boiler Advice Forum on Plumbers Forums.
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