How does my boiler know when my rooms are heated to 20C?

[Johntheo5]

That's true, for a few days/year due to solar gain just in my dining/living room goes few degrees above my required room temperature of 21/22C so I set the roomstat to 24C, it's a digital stat so gives very precise monitoring of room temperature and shuts the boiler down.

 

[JohnD]

When all the rooms are up to temperature they will still require heat to keep them at the setpoint temperature

Even on a hot day? Nonsense.

 

[fixitflav]

Roomstat or not has got absolutely nothing to do with running your boiler in July if/when you have programmed CH/HW, in the summer, when heating is no longer required. you just switch off the heating at the programmer, the boiler will then only fire on HW demand, the CH motorized valve will prevent any hot water circulating through the rads, it seems to me thats how mine works at any rate.

If you have a master roomstat, in a room where it's not too easily satisfied, so the TRVs have something to do, you don't need to do any of that. That's what I have and I don't touch the roomstat or TRVs from one year's end to the next.

 

[Johntheo5]

If you have a master roomstat, in a room where it's not too easily satisfied, so the TRVs have something to do, you don't need to do any of that. That's what I have and I don't touch the roomstat or TRVs from one year's end to the next.

That's what I have, but I have the roomstat in a room where very very occasionally the house temperature rises a few degrees above my highest set TRV which is in my combined dining/living room.

 

[fixitflav]

That's what I have, but I have the roomstat in a room where very very occasionally the house temperature rises a few degrees above my highest set TRV which is in my combined dining/living room.

Does the roomstat switch off the boiler? If it does, your system works like JohnD and I are advocating.
Not quite sure what point you're making about TRV settings. A TRV can control its room to a temperature below or above the roomstat setting.

 

[Johntheo5]

Yes, it does, obviously only if the room temperature reaches its setpoint. A TRV cannot control the room temperature to above the roomstat setpoint if its in the same room like mine, I just use the (one) roomstat in a supervisory capacity for the very odd time that the room exceeds my TRV setting due to solar effect or whatever. Not having any roomstat (or winding it up) will not increase my unwanted boiler runtime by very much as its programmed (switched) off when not needed like from say May to mid September but the HW still operates as required.

 

[fixitflav]

if its in the same room like mine

That's a strange arrangement. I would take the head of that TRV, and if necessary throttle down the lockshield valve to ensure the remaining TRVs have something to do.

 

[Johntheo5]

All my TRVs are controlling as the only TRVs that are set higher are the ones in my combined dining/sitting room that we like to keep at 21C/22C., some of the other rooms are facing North so allways require some heat, if I just used the roomstat then these rooms will not maintain the desired temperature. It has worked very well for me for years, never have to touch the TRV settings, just renew the odd one now and then.

 

[Phigo]

Fit a roomstat in your lounge and remove the TRV in that room, this is the only sensible way to do it.

 

[Johntheo5]

Fit a roomstat in your lounge and remove the TRV in that room, this is the only sensible way to do it.

Sensible in that I then have only control of my "lounge", the other rooms then take what the can get?. (there is a roomstat in my lounge, used in a supervisory capacity).

Evohome whom some consider the bees knees in room control cycles the boiler on/off continuously up to 6 times/hour, my (oil fired) boiler burner often stays off for 15 minutes or more due to the sometimes very low flowrate and its heatexchanger buffer of 20L or more.

 

[Phigo]

Sensible in that I then have only control of my "lounge", the other rooms then take what the can get?. (there is a roomstat in my lounge, used in a supervisory capacity).

Evohome whom some consider the bees knees in room control cycles the boiler on/off continuously up to 6 times/hour, my (oil fired) boiler burner often stays off for 15 minutes or more due to the sometimes very low flowrate and its heatexchanger buffer of 20L or more.

Sensible in the control of your bank account, if you can afford to continue with your method then do so.