Found the problem the heat exchanger had a slight leak £300 for a new one and no one has one in stock so poured some leak sealer in the system and it has been running as sweet as a nut since not lost any pressure over the last week so fingers crossed. :wink:
My friend has a Procombi CT25 and he asked me if I could help him find out why it is losing pressure.
we first renewed the safety valve with no success checked the pressure vessel and pressurised it to 1bar , closed the flow and return valves off to check to see if the pressure loss was on the...