New boiler, TRV's and weather compensation monitor

Midden82

ThisIsWeird said:

Midden82 said:

May I first say your an absolute angel for writing all that to help me understand, thank you so so much🩷
It did make sense so thank you, I know I can be a bit simple at times and it frustrates people but you explained it all so well, I'm not very smart unless it comes to actually doing something and I only have to watch it once to be able to do it myself but stuff like all this has me stumped.
Thankfully I do have a working boiler currently so I'm very thankful for that, the only reason we are getting a new one is the current one is over 20 years old now and it's being moved to a different room, we have an absolute pea sized kitchen and putting the boiler else where is going to free up so much needed space.
I did have one question though, I'm really sorry as I don't want to take up yet more of your time after you've been so lovely.
But is the "weather compensation" and "OpenTherm" an either or thing as in you can only have one or the other? Or are there makes and models of combi boilers that do both.
I am very keen to have Smart TRVs for all the reasons you explained so I do know and understand that bit.
Thank you again for taking the time to explain it for me.
It's all very daunting as it's a large expenditure that needs to last for many many years and I'm worried and anxious that I will make the wrong choice and mess it all up.

You are most welcome, and thank you for your lovely thank you :-)

As far as I know, Weather Comp and Opentherm are quite different things, and used to be separate. I suspect, however, that they may come under the same Smart control system on some boilers.

To be clear - 'Weather Compensation' is simply that - it tells the boiler to go higher or lower to compensate for the outdoor temp. This used to require an outdoor temp sensor. 'Opentherm' is the indoor boiler control, a more complex way for the 'Programmable Room Thermostat' to communicate with the boiler. 

Your current room stat is almost certainly an 'on/off' device, in that all it can do is tell your boiler, "On...on...stay on...that's it...keep going...stay on... Ok! The room has reached temperature! Click! Off! Off! Off, darn you..." sort of thing. 

Opentherm, and other such systems, will instead tell the boiler to adjust it's output depending on how close to the room temp it is; "It's cold! Fire up - full blast! That's it. Niiiice. OOokkaaay, we are getting close to the room temp required; time to back off a wee bit (like turning down a gas hob); that's good, a bit more, sloooowly.. Right - we've reached temp! Try and keep it there, just ticking over". That latter method will save you a small amount on gas consumption, and tend to also give you a more stable room temp. 

Where the two things might overlap is with some Smart systems where the 'weather' is not measured by a sensor fitted outside your house, but is actually taken from weather reports from the Internet. So, that kind of control will most likely have both things going on together.

But FreeBear knows a lot more about this than I do.

You both have been so wonderfully helpful I really can't thank you enough.
Youve explained everything in such a great way that even my crappy brain can actually under it all.
You've been so wonderful and I know this question is perhaps asking if you like marmite but is there a boiler you would recommend to someone as simple in the head as me.
I'm sorry to keep bothering you and taking up so much of your time and of course I don't actually know you but and I'm really really sorry as  this might sound super weird and stalkerish but I actually feel like I can trust you to give me your honest opinion.

Midden82

FreeBear said:

ThisIsWeird said: Your current room stat is almost certainly an 'on/off' device, in that all it can do is tell your boiler, "On...on...stay on...that's it...keep going...stay on... Ok! The room has reached temperature! Click! Off! Off! Off, darn you..." sort of thing. 

Opentherm, and other such systems, will instead tell the boiler to adjust it's output depending on how close to the room temp it is; "It's cold! Fire up - full blast! That's it. Niiiice. OOokkaaay, we are getting close to the room temp required; time to back off a wee bit (like turning down a gas hob); that's good, a bit more, sloooowly.. Right - we've reached temp! Try and keep it there, just ticking over". That latter method will save you a small amount on gas consumption, and tend to also give you a more stable room temp. 

Where the two things might overlap is with some Smart systems where the 'weather' is not measured by a sensor fitted outside your house, but is actually taken from weather reports from the Internet. So, that kind of control will most likely have both things going on together.

But FreeBear knows a lot more about this than I do.

Yup, that pretty much explains what OpenTherm does - Virtually all boilers do OpenTherm, but some manufacturers have adopted their own version of it which is incompatible and ties you in to using their controls if you want anything more than basic on/off control.

Weather Compensation is often done by the boiler, so all you need is the external sensor and no additional "smarts". You can also use a smart thermostat to handle weather compensation by pulling data from the internet. But this is reliant on the internet and web site being available 24/7 for the lifetime of your boiler. Then there is the chance that the web site will introduce a subscription to access the data... Stick with an outdoor sensor attached to the house, and keep all the processing local to the boiler & thermostat.

You both have been so wonderfully helpful I really can't thank you enough.

Youve explained everything in such a great way that even my crappy brain can actually under it all.

You've been so wonderful and I know this question is perhaps asking if you like marmite but is there a boiler you would recommend to someone as simple in the head as me.

I'm sorry to keep bothering you and taking up so much of your time and of course I don't actually know you but and I'm really really sorry as this might sound super weird and stalkerish but I actually feel like I can trust you to give me your honest opinion.
I have sent this to you both as I don't know how to include you both in one comment.
I am having a really tough time with my anxiety and stress.
My brain is never quite and always has like 20 things running through my brain which is why I find it hard to shift through all the details and everyboiler says something different or calls things by other names.
One of the other things that drew me to the valliant is it had stuff in the name which I recognised.

ThisIsWeird

Midden82 said:

You both have been so wonderfully helpful I really can't thank you enough.
Youve explained everything in such a great way that even my crappy brain can actually under it all.
You've been so wonderful and I know this question is perhaps asking if you like marmite but is there a boiler you would recommend to someone as simple in the head as me.
I'm sorry to keep bothering you and taking up so much of your time and of course I don't actually know you but and I'm really really sorry as  this might sound super weird and stalkerish but I actually feel like I can trust you to give me your honest opinion.

Again, you are most welcome - and that's why we're here, so you're hardly imposing on us :-)

As to a recommendation - alas, I've no idea, as I haven't looked into them for a good while.

As far as I know, most boilers these days are pretty well-sorted, and should give many years of reliable service. It'll likely come down to - obviously - 'reliability', and then 'cost', and then features such as the sensitivity of the controls in order to save you as much fuel as possible, but others will need to come up with actual makes and models.

Oh, and length of warranty too - although you'll be expected to have annual services in order to maintain it.

jennifernil

Vaillant is generally well regarded, we have had 3 of their boilers in our Guide Hall for several years and they have been very reliable.   

Personally, we have, in the last 2 years, gone with  Viessmann boilers (as suggested by Freebear) as they have a good reputation too, in fact we have replaced both the 35 year old Potterton boilers we had with Viessmann 100 s, a  32kw, in the main house and a  10kw in the “granny flat”.

  They are both heat only types  rather than combis, so we also have 2 HW tanks.  Our installer has obtained a 12 year warranty on the boilers. We decided on them as they have stainless steel heat exchangers, and are easy to operate.

We have now also installed Tado smart controls, one for each boiler, with Smart TRVs, so each room can call for heat from the boiler when required.  We already had regular TRVs on our system so it was quite easy to do.  We do not use a central thermostat, never have done, the TRVs in each room are set to the times and temperatures we require and this is done using our i pads or phones.  Times on the water heating are set independantly of the CH.

After trying out the Tado system in our home, we have  now also fitted Tado controls at our Guide Hall, so I can sit at home and alter the settings and times if required, rather than have to make a special trip to the Guide Hall should a meeting be cancelled.

Our daughter has a Hive system, with smart TRvs , that operates in a similar manner.  It seems more complicated than the Tado, and she is  apparently not entirely happy with it, but is persevering as it was a big initial investment.

Midden82

jennifernil said:

Vaillant is generally well regarded, we have had 3 of their boilers in our Guide Hall for several years and they have been very reliable.   

Personally, we have, in the last 2 years, gone with  Viessmann boilers (as suggested by Freebear) as they have a good reputation too, in fact we have replaced both the 35 year old Potterton boilers we had with Viessmann 100 s, a  32kw, in the main house and a  10kw in the “granny flat”.

  They are both heat only types  rather than combis, so we also have 2 HW tanks.  Our installer has obtained a 12 year warranty on the boilers. We decided on them as they have stainless steel heat exchangers, and are easy to operate.

We have now also installed Tado smart controls, one for each boiler, with Smart TRVs, so each room can call for heat from the boiler when required.  We already had regular TRVs on our system so it was quite easy to do.  We do not use a central thermostat, never have done, the TRVs in each room are set to the times and temperatures we require and this is done using our i pads or phones.  Times on the water heating are set independantly of the CH.

After trying out the Tado system in our home, we have  now also fitted Tado controls at our Guide Hall, so I can sit at home and alter the settings and times if required, rather than have to make a special trip to the Guide Hall should a meeting be cancelled.

Our daughter has a Hive system, with smart TRvs , that operates in a similar manner.  It seems more complicated than the Tado, and she is  apparently not entirely happy with it, but is persevering as it was a big initial investment.

Thank you ☺️ I must admit I did look in to Hive which recommended by a contractor but from what research I did it seemed like there was a lot of mixed reviews on it some saying how amazing it is but then equally alot of people saying how terrible it is.
I definitely know I'd like to replace my current combi for another combi.
I definitely don't want something with lots and lots and lots of different modes and settings, I'd like something fairly simple so I can just set my TRVs in each room to my desired temperature and then basically forget it knowing that it will just do it's thing.
But then I'm very keen to have to either the "weather compensation" or as FreeBear has mentioned the "OpenTherm" so that I know we're not wasting energy and it's being kind to the boiler and not stressing it out.
And I'd like to be able to look at the boilers stuff on my phone so I can make sure everything is working as it should and if anything is wrong I can catch it before things go bad, and also sometimes if I'm feeling chilli I can boost the heat in the room I'm in.
I have looked at Tado and I really like the variety of devices and the extensive range and that it can work with my Alexa devices and Tado seems to be quite well regarded.

ThisIsWeird

Useful stuff from Jennifernil.
I'm not familiar with Tado, but do have Hive. Although the Hive is perfectly fine for my use (and I've also installed a couple in a local hall!), I cannot recommend it here as it doesn't have Opentherm or similar - it simply turns the boiler on and off as required. 
Viessman are getting votes, then, so I'd look to see what sort of Smart controls work best with it.
Envious of Jennifer's fully-Smart TRV system - that's the ultimate!

FreeBear

ThisIsWeird said: Viessman are getting votes, then, so I'd look to see what sort of Smart controls work best with it.

Baxi also do OpenTherm compatible boilers (but do check specific models, as I don't think all are) - If you are budget conscious, perhaps worth a look, but minimum output is not as good as the likes of Viessmann.

jennifernil

Midden82 said:

jennifernil said:

Vaillant is generally well regarded, we have had 3 of their boilers in our Guide Hall for several years and they have been very reliable.   

Personally, we have, in the last 2 years, gone with  Viessmann boilers (as suggested by Freebear) as they have a good reputation too, in fact we have replaced both the 35 year old Potterton boilers we had with Viessmann 100 s, a  32kw, in the main house and a  10kw in the “granny flat”.

  They are both heat only types  rather than combis, so we also have 2 HW tanks.  Our installer has obtained a 12 year warranty on the boilers. We decided on them as they have stainless steel heat exchangers, and are easy to operate.

We have now also installed Tado smart controls, one for each boiler, with Smart TRVs, so each room can call for heat from the boiler when required.  We already had regular TRVs on our system so it was quite easy to do.  We do not use a central thermostat, never have done, the TRVs in each room are set to the times and temperatures we require and this is done using our i pads or phones.  Times on the water heating are set independantly of the CH.

After trying out the Tado system in our home, we have  now also fitted Tado controls at our Guide Hall, so I can sit at home and alter the settings and times if required, rather than have to make a special trip to the Guide Hall should a meeting be cancelled.

Our daughter has a Hive system, with smart TRvs , that operates in a similar manner.  It seems more complicated than the Tado, and she is  apparently not entirely happy with it, but is persevering as it was a big initial investment.

Thank you ☺️ I must admit I did look in to Hive which recommended by a contractor but from what research I did it seemed like there was a lot of mixed reviews on it some saying how amazing it is but then equally alot of people saying how terrible it is.
I definitely know I'd like to replace my current combi for another combi.
I definitely don't want something with lots and lots and lots of different modes and settings, I'd like something fairly simple so I can just set my TRVs in each room to my desired temperature and then basically forget it knowing that it will just do it's thing.
But then I'm very keen to have to either the "weather compensation" or as FreeBear has mentioned the "OpenTherm" so that I know we're not wasting energy and it's being kind to the boiler and not stressing it out.
And I'd like to be able to look at the boilers stuff on my phone so I can make sure everything is working as it should and if anything is wrong I can catch it before things go bad, and also sometimes if I'm feeling chilli I can boost the heat in the room I'm in.
I have looked at Tado and I really like the variety of devices and the extensive range and that it can work with my Alexa devices and Tado seems to be quite well regarded.

Replacing like with like , or combi  with combi , will be the least expensive option, which is one reason why we stuck with a heat only boiler, the other being the fact that we have a large house with 3 bathrooms, so did not want a combi anyway.

The Viessmann boilers, like all other brands I expect, also come in combi versions, and in various levels of sophistication.  We chose the 100 range as it had good features, and we did not feel that we needed the features of the more expensive range.

For the Tado controls we began with the wireless starter kit and the number of smart TRV heads we thought absolutely necessary,  buying them in various quantities, I think we bought 2 packs of 4 at first for the main house, then another pack of 4 a few weeks later.   Or it may have been 4 packs of 3 in total,  difficult to remember now!     We do have 12 in total.     We also have 3 radiators in rooms we very rarely heat where we have just left the manual TRVs set very low, and one small radiator in one end of the hall which has no TRV at all as it is our original bypass radiator.

The granny flat only has 5 radiators, so needed the starter kit plus 4 smart TRV heads, the 5th radiator again being the original bypass one, a small one in the hallway.

 There were 2 types of  smart TRV heads when we bought ours, not sure if there still is, we have the slightly more expensive model.   Lots of places sell them, so be sure to find who has the best price and make sure it is for the model you want.    Some on line sellers do not make it clear which model they are giving a price for. They just replace the manually operated TRVs, which you will need to have fitted anyway.

If you have 2 or more radiators in one area you can group them as one “room” and designate one to be the measuring device, which saves on the number of rooms you need to set a schedule for.  It can be daunting at first to figure it all out, but once you have set up all your times and temperatures it is easy to  operate, and to make alterations.

Albermarle

Personally, we have, in the last 2 years, gone with  Viessmann boilers (as suggested by Freebear) as they have a good reputation too, in fact we have replaced both the 35 year old Potterton boilers we had with Viessmann 100 s, a  32kw, in the main house and a  10kw in the “granny flat”.

32KW is very powerful for a heat only boiler. Probably a bit overspecced unless you have about 10 bedrooms !
A typical 4 bed semi ( even with 3 bathrooms) should be OK with 15/18Kw for heating and hot water.

OP - Around 32KW would be typical though for a combo boiler, as it needs that extra power to heat up the hot water almost instantly.

ThisIsWeird

I suspect a typo