Thanks beenthere, I was going to let the towel warmer just piggy back of the thermostat in the house so when the house calls for heat the water would just run through the towel warmer. The bathroom is 7 X 9 so I not sure what heat output the towel warmer has, but is there anything like a bathroom that is too warm
? Good point on the coils being more restrictive and maybe not getting enough flow. The hydroaire is 3/4 inch pipe, maybe I could use 1/2 on the towel warmer to make more restrictive? Or just a ball valve that I could manually tweak once or twice on the coldest winter day on the towel warmer . Yes, I have zone valves on the system, but not sure what you mean by Twinning. When the house zone opens the towel warmer zone would open at the same time no choice on that in this setup. Is what your saying to make a completely independent loop for the towel warmer?