I have a Tarm 402 boiler (30+ y.o.) in which the domestic hot water coil is badly calcified. So far, I haven't had any luck finding a new one and am considering acidizing what I have. I'd really rather not do that, would rather replace it.
A flat plate heat exchanger was suggested to me and my only experience with them is in an industrial setting (big ones). As far as I know, they require a powered flow of hot water from the boiler to provide the exchanged heat for the domestic hot water. If someone can explain a proper setup, I'd appreciate it.
What I like about the immersed coil is that I don't have to run a pump of any sort to have domestic hot water during the summer when I'm not heating the house, only build enough fire to heat the boiler contents (about 45 gallons), which provides me with a day's worth of hot water via the coil. My system is quite simple--boiler/one zone valve for the house baseboard convectors/baseboards/no heat storage tank.
I'm open to all ideas and suggestions and thanks to all who respond.
A flat plate heat exchanger was suggested to me and my only experience with them is in an industrial setting (big ones). As far as I know, they require a powered flow of hot water from the boiler to provide the exchanged heat for the domestic hot water. If someone can explain a proper setup, I'd appreciate it.
What I like about the immersed coil is that I don't have to run a pump of any sort to have domestic hot water during the summer when I'm not heating the house, only build enough fire to heat the boiler contents (about 45 gallons), which provides me with a day's worth of hot water via the coil. My system is quite simple--boiler/one zone valve for the house baseboard convectors/baseboards/no heat storage tank.
I'm open to all ideas and suggestions and thanks to all who respond.