[bdcs]

IIRC my thermodynamics classes correctly, the heater would be optimally placed on the hot effluent out of the heat exchanger (HE) going into the house. This is because the COP is improved (similarly to heating the cold side) because the hot side of the HE doesn't need to be as hot to get to the same T, but also the HE doesn't need to move the heat through it, increasing efficiency. (COP decreases with increasing heat flux [Q] in practice.) For well-mixed air in a house (a poor assumption), this is the same as throwing the miners in a closet. I would suggest to the author to move the miners to the hot side the HE going into the house's rooms. Simulation or measurements (over the course of a week, not just instantaneous measurements) would be helpful here .

If I were a HVAC company with WiFi thermostats, I would look into including miners in heating solutions.