How hot of water are you able to achieve? Refresh rate from cold to hot?
Discussion
It got it up to 130f. The refresh rate is what I'm working on right now with the overclocking. It definitely takes longer than the heating elements.
If space isn’t an issue, you could use two tanks, using the miner tank as a preheater.
I actually have a second tank that I was planning on plumbing in series that way I would have 80gal of water and since it can get up to 130f (probably hotter if I want) I would have enough hot water in most instances and the slow recovery time would be fine. Ideally, I would just be hashing 24/7.
My thought would be to use the miner tank first as a pre heater feeding the standard electric tank. If the miner is efficient enough the second tank(w/elements) wouldn’t be doing anything but storing that water. But if the miner doesn’t keep up with usage, you wouldn’t know that at the tap.
Have you messed around with introducing the hot water from the heat exchanger towards the bottom of the tank, maybe the cold side of the water heater down the dip tube with a check valve on the house side? It seems to me it may be more efficient at heating the water in that tank vs putting it at the top via the t&p relief. Heat rises and the top of the tank is the first to get hot.