So maybe we need to return to basics? Central heating has a central heater and the heat is distributed around the home using air, water, or steam, I have never classed storage heaters as central heating where they are individual units, only where there is a central heat store and the energy is distributed and controlled with either air or water is it central heating.
A boiler produces steam which was piped around the premises, however I have not seen steam used in domestic, but the old Lancaster boiler was a common sight. Today we don't boil the water, but the name has stuck.
My first house used hot air not water, and because the air was circulated around the house a single thermostat was able to control the temperature in all rooms, circulating air past single glazed windows however resulted in heavy losses, so expensive to run, second house was open plan, designed to have one central gas fire, and the heat would go up open plan stairs to all bedrooms too. However there was no thermostat on the gas fire, so it was supplemented very quickly with central heating using micro bore.
It had problems in that the bedrooms got too hot, but TRV on bedroom radiators cured that, and again since open plan one thermostat controlled whole house, the fan assisted radiator was moved, it was under the stairs, but it sent too much heat up the stairs, so moved to the front door, that was the only downstairs radiator with a thermostat.
Both houses the central heating worked well, even if first house was expensive to run.
Dads house was very different, there were doors on the down stairs rooms, each room originally had coal fires, these were changed to coke fires, but there was a major design fault, there were no vents to allow combustion air into the rooms by the fires, so they caused huge drafts, and the steel works closed, so also the supply of cheap coke, so central heating was fitted, because the flue was balanced it removed the problem with drafts, however it was really manual control, my parents would hourly alter the thermostat, where in my house the programmable thermostat was never touched.
When my dad died and I was left looking after my mother I realised she was constantly altering the thermostat, and she complained her down stairs bedroom was cold, found near every lock shield valve wide open, up stairs was unused so closed all TRV to frost protection and fitted a heavy curtain in front of the stairs.
However although I get the bedroom warmer having a thermostat in the hall I found the living room varied hugely, I realised it was mainly due to bay windows and the TRV was too slow acting, when the sun came out within an hour the room would shoot from 21°C which I have set TRV to, and reach 25°C some times even higher, first idea was move thermostat into living room, improved, but not really a success. Once I moved to electronic TRV heads then stopped the room over heating.
However since the eTRV head could be programmed, I tried setting the temperature to vary letting the living room cool at night, and bedroom cool during the day, found fabric of house stored too much heat, on a very cold night the room may cool to 17°C but eTRV head set to 16°C, and then in the morning the hall thermostat would turn off boiler before rooms had heated up. So second programmable thermostat fitted in kitchen, this was to keep boiler running for longer in the morning.
However the hall temperature and so also the wet room would plummet when front door opened, and then take an age to recover, open the lock shield valve and hall would get warm and rest of house cold, close the valve and hall cold, there was no TRV in hall, kitchen, or wet room.
So against all the advice given here I fitted a TRV to hall radiator, it was like magic, after years trying to balance the temperatures and get the house to automatic adjust temperatures without continually altering the thermostat I had finally got it to work, front door opened and the TRV would also open and reheat hall, but before the wall thermostat switched off the whole of the central heating the TRV would close again so only on the warmest day would the wall thermostat turn off the boiler. At last it worked.
However my point is my father paid for central heating to be fitted twice, second time the cold water tank was leaking so he moved to a combi boiler and did away with the water tanks. Both times the control was rotten, two different firms, both large, not sole traders, and neither time did it work properly. The plumbing was fine, except for power shower on mains water supply, but that was fixed FOC, well I had to buy a new regulator for shower but they fitted it.
But they seemed to have no idea how to control the heating, second time fitted the boiler was a modulating type, it would work with a modulating thermostat but the hard wiring for thermostat was ripped out and a wireless one fitted, good quality yes, but it would never have controlled the two main rooms as fitted.
They advertised as heating engineers, they were simply pipe fitters, even the solder was lead free so could not call them plumbers. Fitting 36" steel pipes a pipe fitter is a highly skilled guy, I have worked with them pre-heating and stress reliving the pipes, but 15 mm you could kick into place. Not that it needed 15 mm. The pipes are exposed with little or no attempt to hide them. I just hope my dad got two cowboy firms.
My brother-in-law had a system fitted and that clearly showed some people do have the skill, twin water tanks with solid fuel, solar and LPG all used to heat the house, I never questioned how it all worked, as it did, you only question it when it don't work. How my dad let them get away with if I don't know, he spent his whole life working with steam and heating systems, he ran the power station in a steel works, that's a real power station controlling steam, water, gas and electric around the steel works, not just electric. He knew all about boilers, and he told me no such thing as a condensate boiler, you can't extract the latent heat of evaporation in a boiler producing steam, and if it does not produce steam its not a boiler, it is just a water heater.
