I wish I had known these things when I first built my system.
I made my own unpressurized storage system and copper heat exchanger coils like STSS ones. I used a coil winding rig that I saw here and tied them up with high temp plastic pipe and tie wraps, something else I saw another person here doing.
Well it turns out that plastic tie wraps don't like 170+ water over extended periods of time. I couldn't figure out why I was only getting 150 degree water out of the tank when it clearly said it was 170 at the top. When I opened up the tank for a peek I saw that all of the tie wraps had broken and the coils had accordioned to the bottom, so for practical purposes I was only using the bottom half of the tank.
So over the weekend I had to drain the tank down most of the way, don my swimsuit and re-tie all four coils (two for the boiler, one for DHW and one for future solar) with copper supports and 14 ga copper wire. All of the plastic tie wraps were brittle and would crumble in your hand.
Bottom line: really think about the high temp application when you design a system.
Greg H
I made my own unpressurized storage system and copper heat exchanger coils like STSS ones. I used a coil winding rig that I saw here and tied them up with high temp plastic pipe and tie wraps, something else I saw another person here doing.
Well it turns out that plastic tie wraps don't like 170+ water over extended periods of time. I couldn't figure out why I was only getting 150 degree water out of the tank when it clearly said it was 170 at the top. When I opened up the tank for a peek I saw that all of the tie wraps had broken and the coils had accordioned to the bottom, so for practical purposes I was only using the bottom half of the tank.
So over the weekend I had to drain the tank down most of the way, don my swimsuit and re-tie all four coils (two for the boiler, one for DHW and one for future solar) with copper supports and 14 ga copper wire. All of the plastic tie wraps were brittle and would crumble in your hand.
Bottom line: really think about the high temp application when you design a system.
Greg H
