Can't help but think a PRV (pressure relief valve) installed on the return side of the radiator, relieving back into the return line after the thermostatic valve would be a good safety measure to prevent over-pressurizing the radiator if there's not enough heat transfer to cool the return liquid and allow for the thermostatic valve to open. I'm assuming a circulation pump is used to move the heated liquid around the house and therefore you might be causing deadheading of the pump causing pre-mature failure of the pump if return flow is restricted. *I can say with complete ignorance, I haven't watched the videos showing the rest of your setup yet, so forgive me if you've mitigated this elsewhere.*
Great comment...very obvious you know a bit about hydronic systems 🙂. The way I've designed the system is the main fluid flow is through a larger loop containing the main dry cooler. This loop is sized to prevent deadheading of the pump, or overheating of my miners. This is the 'normal' operation of the system. The garage heater in this video is a lower-resistance bypass of this main loop with the thermostatic valve regulating how much fluid goes through this bypass path. When it is mostly closed, the main loop takes all the flow (normal operation) and when it is open, more fluid goes through the lower resistance bypass which is easier for the pump. In either case, the system keeps fluid flowing and the pump happy (and my miners cool).
