I have an old Grant Euroflame (Gemini) oil boiler (1980s?) running DHW and CH. When the system is off the header tank is quiet. When the DHW or CH is running the header tank inlet is running (not dripping: a slow flow) and there is air getting into the system. The air rushes and gurgles through the system when it fires up. When the system goes off the header tank soon stops. The pipework that is common to both systems is visible in the boiler room and there is no leakage. The only place I can think the water is going is up the flue, but while there is some 'steam' from the chimney, it isn't clouds of steam. The inside of the boiler is fairly clean and there is no sign of a leak; although there is some corrosion it is not too bad and cleans up. It seems to me that there must be a hole in the heat exchanger but could there be another explanation?
The system does not have a vent or a pipe going to outside. The only vent path is through the feed pipe. There is a vent pipe over the header tank but it is from the hot water tank.
The pump is sucking through the boiler but the feed line is just upstream of the boiler, so the boiler should be under pressure. The primary circuit feed line is always cold (in a hot boiler room) so I am wasting a lot of energy somewhere and my system is corroding.
The system does not have a vent or a pipe going to outside. The only vent path is through the feed pipe. There is a vent pipe over the header tank but it is from the hot water tank.
The pump is sucking through the boiler but the feed line is just upstream of the boiler, so the boiler should be under pressure. The primary circuit feed line is always cold (in a hot boiler room) so I am wasting a lot of energy somewhere and my system is corroding.
