D
Doggit
Or do TRVs restrict/stop the flow even if the trv is on max?
Well, if you think about it. If the heads set to max, then it's doing the job that it's designed for, so is taking it off, going to improve things at all. The only point about taking the head off (if you place the thermostat in the room), is that you won't get some idiot trying to adjust it.