One thing I have noticed is that the two miners that don’t like something about immersion. They’re performing about 2% less than the other two “good ones”. They tend to oscillate, noticeably, with the ambient temp outside (cooler outside, cooler oil). I think the temps outside in the winter and cooler months could become an issue by cooling the miners too much. The two under performing miners tend to have closer to advertised hashrate when the temps are hot outside.
I know when they are air cooled the software KEEPS the outlet temps at exactly 65C at a min (on one board, the rest just follow and do what they do). That majority of the time they are a fair bit less than this in the oil.
With this information and experience, I think it would be GREAT to control the cooling of the oil. I’m still determining longevity of the miners which is the only thing currently holding me up on pressing forward with heat reclamation. With heat reclamation I could likely control the cooling quite a bit. Depending on where this is at when fall rolls around, I will be installing a switch on the dry cooler to turn the fans on/off individually. This will be manual for now. A variable speed set of fans would be 100% ideal. 3 phase this is easy, but a little trickier with single phase without creating an unnecessary whine from the fans or wasting power.
Ideally, I could create a script to control the fans based off the outlet temp of one of the miners and it would hold the oil at that temp all the time except when really hot and the fans would just run max. This would be better for the miners and reduce power consumption a bit too.
edit: I’m still really liking immersion. It’s a little more stressful, in a sense, due to you’re trying to do something with expensive hardware that it isn’t designed for. I would probably feel better/different if all 4 machines were performing as they should. I also think due to a system that isn’t real sophisticated this adds to it because I’m discussing things like temperature stability. That aspect is completely on me though as I shot for a simplistic and more rudimentary system. I probably would have shot for a different setup having experienced everything (good and bad) at this point.
It’s actually over 100F outside right now. The temp sensor location for the ambient temp is shaded, low to the ground and near the foundation of my home. It tends to run cool by a bit. Ignore the workers online/offline. This is pulling api from PEGA POOL, which just announced they are no longer operating (ugh). I’m back on F2pool for the moment until I get some time to think about which pool I want to use long term.
I think once the big surprise shows up I will do some assessment and start working on some heat reclamation ideas that I can implement. I hate to waste all that heat. I can at least have a very warm garage in the winter I hope to initially get a heater in the garage and also the office/workshop. I will have to run some lines under ground to get to the office, but I’m thinking of running them along where I walk to help keep snow melted as well. The house will be a little more complicated or involved because I don’t want to just throw a big heat exchanger hanging from the ceiling.
I been busy with a few restaurants, a health food store, and a municipal event stage - so I have been neglecting catching up on your progress.
Thanks for sharing your latest project deets.
You could try a hydronic unit heater for your garage. (e-bay) Watch the sone or db rating on the fan!
You could operate the unit heater fan with a wall mounted baseboard heater thermostat.
Another alternative is linear hydronic baseboard heaters. Silent.
Possibly consider insulating the outflowing to the office and use the return flow for de-icing?
Do you have an electric forced air furnace?
If so I would consider placing the coil after the blower, not before, as they are not very good at sucking but work well at blowing.
I would consider the air flow reduction when ordering a coil to be added, The furnace manufacturer may have one they recommend. You still want to be able to move air or else you will strain the blower motor and make your forced air system not move enough air to work properly.
I’ve been able to look through it for about 30 minutes or so. My initial assessment it very good. It is a nice polished product. The fittings look good, choice of material look great, the plate is specifically designed for the antminers.
I’ll go through it more thoroughly through the week and this weekend. I’ll need to plan the switch over to this immersion tank prior to starting to actually hook it up.
One of the things I took a decent look at was the brazed plate heat exchanger. This has 1" inlet and outlets on both the oil and water side. This is opposed to the 1.5" on the asicshield. With that said, based on fairly close measurements, the heat exchanger is approximately 25% larger in volume.
I have decided to create a part 2 thread of this journey. This thread has gotten quite long and also deals a lot with troubleshooting and my endless rambling about things. Please continue the journey here: