Cheapish options for desuperheater water storage.
 

---With the goethermal heating going well, its time to get the desuperheater running. I did have the setup going for a few weeks until I found that the 100 gallon galvanized tank was causing rust in the water. It was known to be rusty inside but was cleaned out well. This apparently is no good. The water comes out clear, but turns orange after hitting the oxygen for a few minutes. So this tank has been bypassed and back to standard electric hot water.
---What are some options for an affordable pre-storage tank that can be pressurized? Poly tanks are out. Buying a new hot water tank is expensive and only half the size of the previous rusty 100 gallon tank. Stainless tanks are expensive. Propane tanks don't seem to be coated inside and would rust. Making some tanks from 12" PVC could work but that pipe is also expensive. I could dig for some used hot water heaters, but who knows when those would start to leak or already be full of sediment. Another other options?

Regards

Jason

I would just use a hot water heater, since by design it's made to hold heated water under pressure and it's insulated.
Another option might be a well water pressure tank with out a bladder.

THey have coatings you can put on the inside of tanks. ATleast I know they do for gas tanks and things might be worth a try?

I’ve used it before on metal gas tanks. It’s a coating you pour in and slosh it all around to coat everything and let dry

Why not just use the existing water heater?

The existing water heater doesn't run much at all after the water is heated. I don't want to rely on the heat pump to keep hot water ready especially after heavy usage. What really helps is feeding it with water that is warmer than from the ground so that it doesn't use so much juice to re-heat after a large amount of hot water is used in one instance.

I like the coating idea. Dump in a gallon of sealant and roll it around for coverage. The trick now is to find a sealant that can be used over rusty steel while be safe for potable water as well as heat resistant for 120F.

I think it might be better (cheaper/easier) to use a non pressurized tank with a pressurized copper coil heat exchanger inside. You could use a stainless steel 55 gallon drum for this, or probably some other containers that aren't rated for pressure. I don't think a clean used stainless steel drum is all that expensive. If you pass your cold water through a short coil of copper tubing in a drum full of hot water, it will get hot pretty quickly. You could use more than one drum to increase your capacity.

You might even be able to use one of those 275 gallon IBC totes the same way, depending on how hot your water temperature is. They are safe to at least 120 degrees, if not more.

Call your local dealers and get a dented special. About 50% off.

This seems the simplest

https://www.youtube.com/watch?v=Bt4kAhtL6Gw

It just took some patience. Found an 8 year old 65 gallon propane water heater on Craigslist for free. Someone was replacing carpet in their basement and decided to replace the tank as a preventative measure. All hooked up and making geothermal hot water again.

Nice find.