My towel rail needs some valves. What's special about "towel rail valves" apart from looking pretty? The ones I've seen don't appear to have thermostatic control. The TRV's which I've seen are all 15mm. This towel rail has 22mm connections. Is the extra bulk of 15mm to 22mm adapters the best solution? I've seen some valves that have 22mm connection but they're not thermostatic.
As the flow connector is high up on the towel rail and the return at floor level, What are the disadvantages of having the TRV on the more easily accessible flow side? TIA