So I got this tank a couple months ago because I had an idea...
And thoughts are welcome. When going over the water holding tank build, I was wondering what to do about lukewarm water. Ya know, that temperature that just doesn't satisfy in the summer because the pipes hanging in your crawlspace have warmed up because it's only 113 degrees outside. I figure our holding tank will experience some heat soak in the summer months. Especially if we're over top of hot pavement a lot.
What if I mounted a small chiller tank within the refrigerator that I put together? A tank that would hold a nice amount of water to keep cold for just the kitchen and bathroom sinks. No need for such cold water in the shower or washing machine, as you're generally running tap water temperature or hotter and refrigerated water would just combat the energy the water heater uses. Cold drinking water is awesome and the volume that we would use wouldn't heat the tank up much as it refills.
Here be my thoughts on materials:
This polished stainless tank is for air suspension and certainly won't be 316. It is made in China (because it says so) and that's where most cheap products come from these days. I have a bore scope that I could poke around the inside with to see how nasty it might be.
We have a reverse osmosis filtration system for the bus (which I'm sure is also made in China) that we may or may not use. I
was ditching the pressure tank from the system. It is aluminum (I'm not sure what grade), has only one small port and its girth is much more than I want to try to squeeze into a fridge.
No matter what metal I use, there's almost always some kind of mineral or acid in water that can degrade it over time, though our rain catchment system and filtration shouldn't be a bother. Buying a tank specifically for such purposes can be quite costly. I'd be down to braze a copper tank to fit my specs. My mind is still wandering on this.
Throw in your two cents because I feel like I'm missing something with this. The basics of the water system are to pump from the holding tank, branch with a manifold to the chiller tank, shower, washer, and water heater, then branch from the chiller tank to both sinks and from the water heater to the sinks, shower, and washer. I'm pretty sure the washer we're getting requires hot and cold hookup.