Going smart on my central heating - advice start to finish welcomed

[danlightbulb]

Ok so I've got a bit more information about the Tado system.

The UK version of the v3 wireless receiver does not support bus connections, but the EU version does and apparently it's possible to order it to UK. There used to be an additional kit to get the bus connections but this has been discontinued.

So I would need to order the EU version of the wireless starter kit which is £200. Whereas Screwfix have the black UK version of the kit on sale at half this price.

I still don't know if my boiler has the EMS connections or for sure whether the Tado can use the EMS protocol.

I'm potentially going to a lot of extra effort here to gain the external modulating functionality - is it worth it because it seems to be fairly uncommon in the UK and products supporting it hard to come by?

 

[vulcancontinental]

Looking at the photographs your heating temperature selector is at a low setting anyway. Your boiler isn't the best at modulating but it will condense a bit and cycle less if left at a low temp. Not sure how configurable the Worcester is but if it allows you to adjust the anti-cycle delay you can lengthen the Off periods which will elongate the ON periods.

If you look out the window and adjust the heating selector according to the weather you become the arbiter of the heating flow temperature, a DIY bus control like OpenTherm or equivalent; adjust it yourself.

Listen to the boiler; how long is the burn time? Longer than 3 minutes you have an efficiency loss of 1.5% or less, every 10 seconds is a 12% loss.

All this is free or spend £hundreds to save perhaps 4%. With a £2000 annual heating bill this represents £80/annum.

 

[Deleted member 267285]

The wiring diagram in the boiler installation manual seems to show an EMS connection plug, although I can't see any indication of it on the boiler front panel.

That’s because it isn’t on the front panel - none of it is, this is the pcb which site behind the front panel and removing the cover on that particular boiler forms part of the combustion circuit, which needs Safety checks to be carried out afterwards.

 

[danlightbulb]

Looking at the photographs your heating temperature selector is at a low setting anyway

Yes because it's currently switched off waiting for a new pressure gauge to be fitted as the current one is broken.

If you look out the window and adjust the heating selector according to the weather you become the arbiter of the heating flow temperature, a DIY bus control like OpenTherm or equivalent; adjust it yourself

This is what I used to do in my old house with similar boiler. In summer I'd set it to 2 or 3, as it got colder and the house wasn't heating up enough I'd increase to 5 or 6 even max in the depths of winter. That's fine but I'm not going to adjust it every day and if I'm going smart controls shouldn't I get one that can give me the full benefits?

That’s because it isn’t on the front panel - none of it is, this is the pcb which site behind the front panel and removing the cover on that particular boiler forms part of the combustion circuit, which needs Safety checks to be carried out afterwards.

Yes I am waiting for an engineer to come and fit a replacement pressure gauge anyway so I can hopefully take the cover off to check the connections then when he comes he will be able to check it's on properly. Although I have to say I find it strange that a flimsy plastic cover can be part of the combustion chamber. It seems to me that it's not fully sealed anyway as all the pipes come out the bottom of it. I've seen other threads where the same has been commented.

 

[Lower]

How big is the house and how many rooms do you want to be vary the temperature in over the course of the day.

Personally, i think smart TRV's are unnecessary unless you have a specific need to heat specific rooms at different times.

Your hall radiator is would normally not be fitted with a trv, so all smart trv's are going to do is let you heat the hall, stairs and landing and then one specific room at a time. Most people don't try to heat their houses that way as it takes time to heat up a room.

 

[Deleted member 267285]

Although I have to say I find it strange that a flimsy plastic cover can be part of the combustion chamber.

I didn’t say it was part of the combustion chamber.

 

[danlightbulb]

How big is the house and how many rooms do you want to be vary the temperature in over the course of the day.

Personally, i think smart TRV's are unnecessary unless you have a specific need to heat specific rooms at different times.

Your hall radiator is would normally not be fitted with a trv, so all smart trv's are going to do is let you heat the hall, stairs and landing and then one specific room at a time. Most people don't try to heat their houses that way as it takes time to heat up a room.

3 bed semi detached. The hall radiator where the stat is does have a trv, the bathroom towel rail does not.

My TRVs need to be replaced anyway (see pictures above). I'm hoping the valves still are ok and I can swap new heads onto them. I don't have to go smart TRVs if it's not worth it, but I thought that they can be used to call for heat in one room only so say for example it's cold in the bedroom at night, we can call for heat just in that room. I don't know how often I would use it, but we are likely to have a fairly cold house because it's solid wall no cavity and the front is north facing.

 

[karlbbb]

This is what I used to do in my old house with similar boiler. In summer I'd set it to 2 or 3, as it got colder and the house wasn't heating up enough I'd increase to 5 or 6 even max in the depths of winter. That's fine but I'm not going to adjust it every day and if I'm going smart controls shouldn't I get one that can give me the full benefits?

They argued it on a value perspective. It'll be several hundred pounds to spend for what'll be less than £80 return per year. I myself would be looking at almost £400 to get just OpenTherm on my dual-zone heating, and if it saves 4% at best, that's £38 a year. It's not a great payback period, and will likely be worse in reality as my boiler is probably 3x too big for my house.

 

[danlightbulb]

They argued it on a value perspective. It'll be several hundred pounds to spend for what'll be less than £80 return per year. I myself would be looking at almost £400 to get just OpenTherm on my dual-zone heating, and if it saves 4% at best, that's £38 a year. It's not a great payback period, and will likely be worse in reality as my boiler is probably 3x too big for my house.

Yeah im now thinking holding back on the smart TRVs and just getting the main controller upgraded. That could be as cheap as £100 if I buy the non EMS capable Tado that's on sale in Screwfix. Or £200 if I try to order the EU version which supports the EMS interface.

I will need to decide if the full load modulation function is worth it. The extra cost of the EU version of the Tado device plus having to access the EMS port under the cover of the boiler.

 

[danlightbulb]

Still undecided on whether to go full on EU version Tado or not.

My boiler manual says set the temperature dial to 1 or 2 to maximise efficiency. This would be 47-50 degrees C according to the manual which I guess maintains condensing mode.

I don't know how the Tado would choose to set the flow temperature. Would it choose to set a lower temperature and bring the house up slowly, or would it choose to set a high temperature and bring the house up to temperature quickly before leveling off. How often would the boiler be operating in condensing mode if I use the Tado device?

I suppose this is the crux with smart stuff isn't it - you've got to hand over the control to the device rather than doing it yourself. Is the device smarter than me adjusting the dial on the boiler when it gets colder?

I dont know what to do. If I buy the UK version of the Tado I can get it for £100, if I buy the EU version it will cost me £200 as the only place I can get it from is the Tado online shop.

I dont understand why there is so little information/best practice about this topic - is it beneficial or not, its not clear.

 

[karlbbb]

Embracing OpenTherm is beneficial, but it's not going to slash your bills. Seems to be around 3% savings which means a long payback depending on your initial outlay and usual annual gas usage.

As for the other question - it'll start the heating cycle on a higher flow temp, then as you approach the set temperature it reduces the flow temperature to avoid overshooting. If your thermostat comes on at 16:00 and wants 20C, and the room is already 19C, it'll do a much lower flow temperature to start with because there isn't a large difference to make up.

Asking how often you'll be in condensing mode is a difficult question, because it'll depend very much on how much energy is being taking from the heating system, outside temperature, return temperature differential etc. The idea is to modulate the flow temperature down and achieve the perfect balance of a steady flow temperature maintained by a constant burn in the boiler at a temperature differential that ensures condensing operation. That's hard to do, as it seems most people's boilers are likely over-sized. Mine certainly is, likely by a factor of 2-3.

 

[Mister Banks]

Based on all the reading i have done, and from asking questions on forums, I have come to the conclusion that these smart heating controls will only save you money if someone else paid for them ! If you want to control your environment using remote devices either home or away and you like the extra information that some smart devices are able to communicate to you then go for it but if you want to save money then stick with your mechanical thermostat and programmer.

Please, if someone knows better than me then tell me I am wrong and why I am wrong.

 

[vulcancontinental]

Based on all the reading i have done, and from asking questions on forums, I have come to the conclusion that these smart heating controls will only save you money if someone else paid for them ! If you want to control your environment using remote devices either home or away and you like the extra information that some smart devices are able to communicate to you then go for it but if you want to save money then stick with your mechanical thermostat and programmer.

Please, if someone knows better than me then tell me I am wrong and why I am wrong.

You're partially wrong because you've been reading the wrong information or not interpreting it correctly.

Where you are correct is that if you spent time constantly adjusting settings and temperatures with a mechanical clock or programmer and thermostats plus the boiler selector you will achieve equal efficiency for the system, you will become a slave to the system.

The latest controls automate things and if you're away there's no need to phone a neighbour and instruct them to make adjustments or tell them you're on your way home or could they turn the heating down as you have forgotten to do it.

Compare the inconvenience to the cost. Without constant attention you will not acheive maximum efficiency.

 

[Mister Banks]

You're partially wrong because you've been reading the wrong information or not interpreting it correctly.

Where you are correct is that if you spent time constantly adjusting settings and temperatures with a mechanical clock or programmer and thermostats plus the boiler selector you will achieve equal efficiency for the system, you will become a slave to the system.

The latest controls automate things and if you're away there's no need to phone a neighbour and instruct them to make adjustments or tell them you're on your way home or could they turn the heating down as you have forgotten to do it.

Compare the inconvenience to the cost. Without constant attention you will not acheive maximum efficiency.

I rarely see the need to adjust anything on my central heating other than occasionally adjusting the room thermostat. I have looked at buying a Hive but I cant see where or how any savings can be made, at least the Hive is cheap (hubless version) in comparison to some so called smart thermostats. I would buy it for its aesthetics more than anything else.

There is a better argument for the ROI given the existing high energy prices but once/if prices go back to where they were than you could be looking at 6-7 years to break even.

 

[vulcancontinental]

I rarely see the need to adjust anything on my central heating other than occasionally adjusting the room thermostat. I have looked at buying a Hive but I cant see where or how any savings can be made, at least the Hive is cheap (hubless version) in comparison to some so called smart thermostats. I would buy it for its aesthetics more than anything else.

There's little doubt you could improve the efficiency of your system, the amount would depend on what components your system is comprised of. If you are content to run it as is, do so at peace but knowing it could be a little more efficient however you don't consider it a worthwhile effort. To buy a heating control on its appearance is to me not the most convincing reason upon which to base a technical purchase.