I have often seen radiators fitted under windows, I assume as furniture is unlikely to cover them, I have never seen a coal fire under a window, and I know many a coal fire was poorly planned, there needs to be a air supply to a coal fire, so on the outside wall allows vents to allow combustion air into room to feed fire without causing drafts, however houses have been built with flues going up centre of house without any ducts to bring in combustion air, it would seem builders have not got a clue how to heat a house and have never had throughout the ages.
Here they have not even got a roof on the house, don't think underfloor heating has ever worked?
If a room is held at a set temperature it really does not matter where the thermostat is, Roger465 is correct, we can compensate for the difference between where measured and where we sit. As long as the heating is analogue controlled with a TRV and modulated boiler flame the place where thermostat is placed does not matter.
However with digital control this changes, hysteresis is the problem, there has to be a difference between on and off temperatures, so when the thermostat switches on, there is a delay before the heat produced reaches the thermostat to turn it off, if the delay is too short, we loose energy through the flue every time the boiler switches off, so it costs more, if the delay is too long, the heat in the room is likely to over shoot. So it is really important where an digital thermostat is positioned.
However the big question, does the digital thermostat control room temperature? or is it to reduce cycling? there is a problem using return water temperature to control a boiler, the boiler needs to fire up and circulate water even on a hot day to find if any heat is required, so fitting a thermostat that switches off the boiler on a warm day is a good idea, to do this it needs to be in a room normally kept cool, so the off temperature can be set low, when it is 20°C outside we don't want central heating to run, so the thermostat needs to be set less than 20°C yet in the living room we often want it at or warmer than 20°C so living room not suitable for the thermostat to stop cycling.
So with in my case Bosch Worcester Wave thermostat will likely control the room it is fitted in A1 where ever it is located, however the instructions say more than 500 mm from ceiling and more than 1200 mm from floor and 1000 mm from door in the reference room. This reference room clearly always needs heating, and there are also EMC considerations as to location.
A reference room is an area (for example the hallway or landing) in which the temperature is measured, which is representative of the whole home and where the most time is spent.
Personally I don't spend most of my time in the hallway or landing, and because the sun effects the temperature of our living room it is not representative of the whole home. I did a find on the installation document for TRV it does not refer to them, however I would assume one is not fitted to reference room?
So although a Wave thermostat is designed to fit my boiler and I would expect if fitted in living room would keep the temperature spot on modulating the boiler through the EMS bus as required, the question is what happens to the rest of the house? I would prefer EvoHome where it takes multi reference points to decide how to modulate the boiler, but Bosch Worcester is not OpenTherm. Also the thread asks about wireless and Bosch Worcester Wave is not wireless. Although it does connect to internet if required.