Should Combi boiler have thermostat?

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Worcester Greenstar 25Si Mk IV

Since its installation 5 years ago; whenever the weather is hot, such as it is now, my Father turns the Heating Temp dial down to the Snowflake symbol, believing this is the lowest setting but the radiators remain hot all the time.

He doesn’t use the timer, as he’s home throughout the day; so normally, the heating is on all the time, which due to normal UK weather conditions, this doesn’t cause a problem but currently, the radiators are hot and my Father house is uncomfortably hot.

Each radiator, excluding the bathroom, have thermostatic valves, set to heat setting 3.


Should the combi boiler have some kind of thermostat which can detect the heat within the house or detect outside weather temperature, which can turn the boiler off and just allow hot water ?
 
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CBW

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Any heating system is usually better with at least a room thermostat. When the boiler thermostat has been turned down previously, have the radiators stayed off?
 
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Thermostat is required for any new installation, and has been for many years.
It was certainly a requirement 5 years ago.

Without it, you are throwing money away.
 
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Is that a separate room thermostat that’s been a requirement or does the Heating Dial on the front of the boiler meet that requirement ?


First time I’ve noticed this but the radiators have remained off this evening.

I initially thought the radiators where remaining fed even though my Father had turned the Central Heating to its lowest setting,

I’m not always there, so not aware when my Father turns the heating down but on a day like today; it absolutely boiling outside, just as hot inside, all the windows and doors open, heating on lowest setting but radiators still hot.

It does appear that the radiators are cooling down but taking so long to do so; and with the hot weather, they’re keeping the rooms exceptionally hot but I’ve never experienced this elsewhere, so I’m convinced something not right.

I’ve believed the TRVs would control the heat within each room and the boiler had a built in thermostat which controlled or prevented the boiler from heating the radiators according to the heat setting selected.

Would it be possible to add a room stat to the current combi boiler.... is it possible/feasible to install one in the living room and one in the front bedroom?
 
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A separate room thermostat, which reacts to the air temperature and switches the boiler off when the room is warm enough.
The control on the boiler just sets the temperature of the water in the radiators, which is unrelated to air temperature or whether heating is actually required. Even on the lowest setting, it will still be using gas to heat the water in those radiators.

TRVs will close off individual radiators when heating isn't required in that room, assuming they are set correctly and haven't jammed open or closed. They are just mechanical valves, there is no connection to the boiler or anything else.
Generally at least one radiator should have been installed without a TRV, but even with all of them closed, the boiler will still try to heat the water in the radiators, the result being that the boiler will cycle on and off all the time causing premature wear and still wasting gas.

One room thermostat can and should be added to the boiler as soon as possible. It's a cheap and fairly straightforward item to install.
Not possible to have more than one without splitting the heating system into two or more zones, which will require alterations to the pipework and additional control valves installing, and will not be worthwhile or useful.
 
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Flameport..... Thanks for your very thorough reply.

Yeah, I knew the TRVs are mechanical and not physical connected to the boiler; they all appear to operate correctly but when turned to heat setting 2, this turns the radiators off completely; and it’s the radiator in my Fathers bathroom which doesn’t have a TRV.
I’ve set the TRVs with the tabs so the radiators can’t be turned up too high or turned off completely.

I’ll look into the installation of a room stat, thanks.
I thought, with wireless technology, it may have been feasible to install more than one within a home.

Thanks
 
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Wireless stats are great, if you want one room to be a master just pop the stat in there, go to bed and need a room hotter take it with you. I would point out that to maximize efficiency an external temperature probe for a boiler is a must, that will set the boiler CH temp to compensate for low temps.setting it low is just a waste of energy, sure the ch water is lower temp but the boiler has to run longer to get the house warm...effectively that knob lets you take over from the computer built in the boiler to do that very job, warm days lower temp cold days hotter.
I would also point out that keeping a lowl temp imbalance between in a house between upstairs and down is desirable, energy flows from hot to cold, rooms that are kept cold will heat up, by sucking heat from the other hotter rooms.As energy travels it disperses and gives up temperature, that's called a draught, sitting in a draught makes us feel cold....so we turn the heating up. Frankly we humans are rubbish at being thermostats.
 
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There are plenty of wireless options available, they each require a base station wired into the boiler.
Once you've got that bit you can put wireless trv heads on the radiators- net result is each room can be programmed with different times and temperatures. All controlled via an App of course (so may not be the best route if your father doesn't like them)
 
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Thanks for all the additional advice and recommendations.

Wireless TRVs on the radiators linked to room stat & boiler sounds good, although a mobile App won’t be suitable for my Father, he still can’t get to grips with the Tv remote, he also has Dementia; also, I’m mistrusting of apps myself now due to background tracking and data grabbing, to supposedly improve user experience.

Also, it won’t be practical to be moving a wireless room stat from room to room, my father will stick in a drawer somewhere, leave it upstairs or somehow lose it.

Thanks again for the suggestions
 

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A couple of pointers: A wireless thermostat can be wall mounted. Removing the case on that boiler needs critical safety checks afterwards as it forms part of the combustion circuit.
 
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If your father is suffering from dementia then get a smart phone compatible wireless thermostat fitted and you will be able to monitor the temp remotely and make sure that he is safe.

Not having one will cost at least 30% on his gas usage and if there isn't a time clock either you're looking at getting on for 50% wastage.

The thermostats primary purpose is to turn the heating off, not on!
 
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Although I’m no longer a fan of smartphone apps; I assume a WiFi connection is required for the smartphone wireless thermostat but is a WiFi connection also required for a wireless room stat to communicate with the boiler?

Also, I knew wireless room stat can be affixed to the wall; another post mentioned taking it to the bedroom when needed etc.

Is an external temperature probe for the boiler an addition to the Room stat or an alternative?

How would the temperature probe be beneficial and how is it connected ?
 
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Although I’m no longer a fan of smartphone apps; I assume a WiFi connection is required for the smartphone wireless thermostat but is a WiFi connection also required for a wireless room stat to communicate with the boiler?

Also, I knew wireless room stat can be affixed to the wall; another post mentioned taking it to the bedroom when needed etc.

Is an external temperature probe for the boiler an addition to the Room stat or an alternative?

How would the temperature probe be beneficial and how is it connected ?
Depending on what exact solution you go for, there will as part of that solution be a box permanently wired to the boiler. The other bits of the system communicate with that box, the box then calls for heat from the boiler as required.
With the Wiser stuff, if you have the WiFi TRVs the room thermostat is redundant as a thermostat. You can use it to call for a temporary boost or to temporarily reduce room temperature setpoint. Other systems are available.
Again the Wiser stuff cheats. Mine doesn't have an external temperature probe so it uses my location and external weather services to determine outside temperature and optimises heating times on that basis.
Most basic timeclocks/controllers won't make full use of an external temperature probe (except possibly for frost detection).
An app based setup might work well in your setup- no dials or knobs or switches to be moved to random settings. You can check on your phone what the system is doing and adjust it remotely from wherever you happen to be if your dad doesn't want the faff.
 
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Thanks again for all the advice and suggestions.

Controlling my Fathers heating through a smartphone, I don’t think it’ll be practical but thanks for the suggestion; also, my Fathers house doesn’t have a WIFi broadband connection.

Also, these wireless TRVs, I assume they can’t be locked to a specific heat setting either, meaning they can be manually turned on or off.

I believed the boilers current mechanical timer module is replaced with a new digital timer module which incorporates a wireless receiver for the wireless room stat.

I also believed the wireless room stat communicated with the receiver module via its own wireless network and not via WiFi ?
 

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