I just purchased a number of used cast iron radiators that I will use to migrate from forced air to all hydronic. I have completed a heat loss calculation for each room in our house and an estimate for btu output for each radiator. I use storage and my boiler system temperature ranges anywhere from 140f to 195f. My design temperature is 140f, so the rads should provide adequate heat on the coldest days while running off storage. My question is, should I supply a constant 140f to the rads using a mixing valve or just use what ever temperature is available from the boiler/storage (140 - 195).
What would be the best approach on this?
What would be the best approach on this?