I have really hard well water at the house. When I put my boiler in, the lab called my water "liquid rock"
and did not recommend I fill the system with it. I ended up hauling water from town and had to figure out a way to top off with the same hauled in water during the heating season. I built this nurse tank and added an inlet on the outside of the boiler with garden hose threads. Basically I hook the nurse tank to the inlet to top off the boiler. I bought the pump at Harbor Freight ($40), the 15 gal tank at an auction ($1), a used washing machine fill hose, and a few plumbing supplies and scrap plywood. I have $50-60 in it and haul water 5 gallons at a time to refill the nurse tank. I store it inside my heated shop and wheel it out to the boiler with a 2 wheeled cart when necessary. I also add some corrosion inhibitor to it to keep the levels up in the stove. works pretty well and something I did not think of, I keep much better track of how much water I have to add to the system.
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