I am replacing an inefective (too small) towel radiator in my bathroom with a proper rad. I have the correct rad, some thermostatic valves and all the bits I need. I'm pretty good with plumbing so am confident to drain the system (I need to do this patially as I have to re route some pipes) and hang/connect the new rad.
However I don't know which side of the rad I should put the thermostatic valve. I don't know which way the water is flowing through the rad as the pipework is hidden. I was under the impression that it needs to go on the inlet side - is this correct? The instructions for the valves don't say if the valve needs to go on the inlet or can go on either side.
So is there an easy way to find out which way the flow goes (I have just thought I could switch the heating on and try and feel on the rad which side gets hotter but as its a tall radiator this might not work - is this a good way of finding out?) and does it really matter?