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I started in a house with hot air gas central heating, the air was circulated, and a single thermostat in the living room worked fine.
Next house was a problem to start with, you adjusted the lock shield valves to adjust the proportion of heat to each room, but open plan house, so temperature of bedrooms depended on if door left open or closed, the advent of the TRV was a god send stopping bedrooms from over heating, but by 1985 all running as sweet as a nut, so never really considered central heating, it worked, that was end of it.
Around 2004 my parents where having problems, I would hear dad complaining his bedroom was too hot, but not until his death and we went to look after mother did I really realise how bad the system was.
There was what seems to be typical problem, the installers had not set anything, all lock shield valves wide open, however the house had a hall and doors to each room, not open plan I was use to, and the big problem was the bay windows, and the sun.
It was then I realised why we needed TRV's, but a real problem is the *123456 marked on them, if room too hot, was the TRV needing adjustment or lock shield valve, what I needed was a TRV with °C marked on it, which I got using Energenie heads, it was not the head which was the great improvement, it was being able to set to 20°C.
But that house made me look at temperature control for the first time, up to then it had simply worked. So it turns out house had a modulating boiler, that means output varies. Theory seemed great, if return water too warm boiler turns down, if too cool boiler turns up, so the TRV was king, it controlled the temperature of every room, except for hall.
However it didn't work, front door opened and boiler turned on, front door closed and boiler turned off, massive radiator in the hall, what ever I did could not compensate for front door being opened. And to be fair, the general instructions for fitting a wall thermostat say fit in a ground floor room with no alternative heating and no outside doors. So kitchen out, cooker in there plus outside door, living room out gas fire in there, best room out gas fire in there, wet room out electric under floor heating in there, hall out as outside door, under stairs out as no heating in it. So not a single room was it seems suitable for a wall thermostat.
It said on every thing I read, do not fit a TRV in the room with wall thermostat, but in desperation I fitted one in the hall. It worked, after some adjustments, and my theory was the TRV set slightly lower than the wall thermostat, but since wall thermostat higher, if front door not opened it will on warm days turn off the boiler, but on cold days the TRV's did all the work keeping each room at temperature set, and wall thermostat would never turn off.
However that was not quite the case, Honeywell Y6630D wireless thermostat has anti-hysteresis software, and as the target temperature is approached, it uses a mark/space ratio to stop the temperature over shooting. That would have worked great in this house with an on/off oil boiler, but not with a modulating boiler, as each time it switched off, on switching back on again the boiler would run flat out, this messed up the working of the TRV's and resulted in boiler being switched off again while running flat out, so heat wasted as it cooled through the flue.
Next step was a programmable wall thermostat a Horstmann HRFS1 and the TRV also replaced for a programmable one, and now cooking on charcoal, however it seems the Horstmann HRFS1 does not fail safe, the Honeywell Y6630D if it looses the RF link closes down, the Horstmann HRFS1 does not, so boiler still switched on as RF link lost.
So the hunt was for a wireless thermostat that did not use mark/space to stop over shoot but also had a fail safe, looking at some thing like Nest, where it works out when to switch off by remembering what happened last time. Or move to cheap wired.
I moved house. And with new house decided to buy Nest Gen 3, as it was claimed to work with the TRV heads Energenie which I had brought from my late mothers house, however it seems Nest had withdrawn support, and so they do not talk to each other.
New boilers likely have OpenTherm, but the old Worcester Bosch did not, so it seems there was no wireless option until looking at £200 plus wireless thermostats. The odd one out is Hive, not a smart thermostat, no cleaver algorithms to work out when to turn on/off, but it does connect to Hive TRV heads, which send a 'demand for heat' which turns the wall thermostat on for 30 minutes, seems great idea, however it seems there has been a RF linking problem with some homes, and Hive has made an extra strong hub to get around the problem.
However hind sight is easy, would have been better to have fitted a cheap programmable wired wall thermostat and cheap eQ-3 TRV heads, but hind sight is easy.
The old Honeywell Y6630D instructions have to be down loaded to read, and not until you read the instructions do you know it used mark/space to stop over shooting, or that it had a fail safe. And it seems to be same with most wall thermostats, you have to down load the instructions before you find out what they do.
This
one was used in my old house, it is designed for heating or cooling, and you can select if on battery failure contacts are open or closed, it has change over contacts, and the two AAA batteries last around 18 months a pair.
However Screwfix advert says 3 wire installation they have changed the add to say SPDT it did say SPST but this is typical, the adds really don't tell you much about the unit.
It seems there is not one size fits all, the EPH thermostats do a master/slave for Opentherm but don't connect the TRV heads, and it seems every system has plus and minus. However unless we talk about the good and bad points, you will not know which works best with each type of installation.
The big problem is a mark/space control from a wall thermostat will control the temperature even with a modulating boiler, but will not do it in an efficient way. So what do you use, and what are it's good and bad points? With some luck maybe we can in the future direct people to this thread, but do give type of home and installation, as said with the old open plan house by 1985 all running A1 and I had no idea of the problems found with houses with doors between down stairs rooms.
Next house was a problem to start with, you adjusted the lock shield valves to adjust the proportion of heat to each room, but open plan house, so temperature of bedrooms depended on if door left open or closed, the advent of the TRV was a god send stopping bedrooms from over heating, but by 1985 all running as sweet as a nut, so never really considered central heating, it worked, that was end of it.
Around 2004 my parents where having problems, I would hear dad complaining his bedroom was too hot, but not until his death and we went to look after mother did I really realise how bad the system was.
There was what seems to be typical problem, the installers had not set anything, all lock shield valves wide open, however the house had a hall and doors to each room, not open plan I was use to, and the big problem was the bay windows, and the sun.
It was then I realised why we needed TRV's, but a real problem is the *123456 marked on them, if room too hot, was the TRV needing adjustment or lock shield valve, what I needed was a TRV with °C marked on it, which I got using Energenie heads, it was not the head which was the great improvement, it was being able to set to 20°C.
But that house made me look at temperature control for the first time, up to then it had simply worked. So it turns out house had a modulating boiler, that means output varies. Theory seemed great, if return water too warm boiler turns down, if too cool boiler turns up, so the TRV was king, it controlled the temperature of every room, except for hall.
However it didn't work, front door opened and boiler turned on, front door closed and boiler turned off, massive radiator in the hall, what ever I did could not compensate for front door being opened. And to be fair, the general instructions for fitting a wall thermostat say fit in a ground floor room with no alternative heating and no outside doors. So kitchen out, cooker in there plus outside door, living room out gas fire in there, best room out gas fire in there, wet room out electric under floor heating in there, hall out as outside door, under stairs out as no heating in it. So not a single room was it seems suitable for a wall thermostat.
It said on every thing I read, do not fit a TRV in the room with wall thermostat, but in desperation I fitted one in the hall. It worked, after some adjustments, and my theory was the TRV set slightly lower than the wall thermostat, but since wall thermostat higher, if front door not opened it will on warm days turn off the boiler, but on cold days the TRV's did all the work keeping each room at temperature set, and wall thermostat would never turn off.
However that was not quite the case, Honeywell Y6630D wireless thermostat has anti-hysteresis software, and as the target temperature is approached, it uses a mark/space ratio to stop the temperature over shooting. That would have worked great in this house with an on/off oil boiler, but not with a modulating boiler, as each time it switched off, on switching back on again the boiler would run flat out, this messed up the working of the TRV's and resulted in boiler being switched off again while running flat out, so heat wasted as it cooled through the flue.
Next step was a programmable wall thermostat a Horstmann HRFS1 and the TRV also replaced for a programmable one, and now cooking on charcoal, however it seems the Horstmann HRFS1 does not fail safe, the Honeywell Y6630D if it looses the RF link closes down, the Horstmann HRFS1 does not, so boiler still switched on as RF link lost.
So the hunt was for a wireless thermostat that did not use mark/space to stop over shoot but also had a fail safe, looking at some thing like Nest, where it works out when to switch off by remembering what happened last time. Or move to cheap wired.
I moved house. And with new house decided to buy Nest Gen 3, as it was claimed to work with the TRV heads Energenie which I had brought from my late mothers house, however it seems Nest had withdrawn support, and so they do not talk to each other.
New boilers likely have OpenTherm, but the old Worcester Bosch did not, so it seems there was no wireless option until looking at £200 plus wireless thermostats. The odd one out is Hive, not a smart thermostat, no cleaver algorithms to work out when to turn on/off, but it does connect to Hive TRV heads, which send a 'demand for heat' which turns the wall thermostat on for 30 minutes, seems great idea, however it seems there has been a RF linking problem with some homes, and Hive has made an extra strong hub to get around the problem.
However hind sight is easy, would have been better to have fitted a cheap programmable wired wall thermostat and cheap eQ-3 TRV heads, but hind sight is easy.
The old Honeywell Y6630D instructions have to be down loaded to read, and not until you read the instructions do you know it used mark/space to stop over shooting, or that it had a fail safe. And it seems to be same with most wall thermostats, you have to down load the instructions before you find out what they do.
This
one was used in my old house, it is designed for heating or cooling, and you can select if on battery failure contacts are open or closed, it has change over contacts, and the two AAA batteries last around 18 months a pair. However Screwfix advert says 3 wire installation they have changed the add to say SPDT it did say SPST but this is typical, the adds really don't tell you much about the unit.
It seems there is not one size fits all, the EPH thermostats do a master/slave for Opentherm but don't connect the TRV heads, and it seems every system has plus and minus. However unless we talk about the good and bad points, you will not know which works best with each type of installation.
The big problem is a mark/space control from a wall thermostat will control the temperature even with a modulating boiler, but will not do it in an efficient way. So what do you use, and what are it's good and bad points? With some luck maybe we can in the future direct people to this thread, but do give type of home and installation, as said with the old open plan house by 1985 all running A1 and I had no idea of the problems found with houses with doors between down stairs rooms.
