I've got a Ferolli Modena 102 which has got water constantly coming from the overflow pipe. The pressure is sitting at around 3 and the filling loop is disconnected so it seems to be drawing water in from the mains. Could this just be the expansion vessel that needs replacing/recharging or is it more likely the exchanger is perforated? What pressure should the expansion vessel be recharged to?
your preasure should be sitting about 1 to 1.5 bar when cold. it could be the safety blow off that is running should tell you on the vessel what the recharge pressure is.
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