Vokera 29ci opentherm module?

waqasahmed

I have this boiler 

https://www.boilerguide.co.uk/productinfo/vokera/easi-heat-plus-29ci-combi-gas-boiler

Vokera have said

"The boiler stated needs an additional interface plug for load compensation control, we cannot guarantee the operation of the boiler with a 3rd party opentherm control, However if the control is working as an on/off control and is volt free switching this can be suitable"
"

I'm not sure where you can buy the modules? And would it still be worth it to get radiator smart TRVs if my boiler theoretically supports opentherm? (I'd get a smart modulating thermostat) 

waqasahmed

Does anyone know a company that might be able to help? 

Bendy_House

Hi Was.

I don't know - sorry.

From what I understand, 'Opentherm' is a universal system, so if you have an Opentherm Prog Stat, it should be usable on any Opentherm-enabled boiler.

I think, but don't know.

I'm also not sure what Vokera are actually saying there. Is it that you need an 'interface plug' added to the boiler so that it becomes Opentherm-enabled, and then you can add your Opentherm controls - presumably from a number of manufacturers? I suspect it is. But don't know.

This is specialist stuff, and I'm not sure if this forum will p[rovide it. We do have a few plumbers on here, but don't know how often they view.

Might be worth a specialist plumber's forum? I have used this in the past - https://www.plumbersforums.net - and generally got the info I required.

There are others too. Some might even have a specific Vokera section?

BUFF

probably a daft question but have you contacted Vokera to ask what exactly you need, availability & cost?

whether it is worth it depends upon what your existing control system is & how you use it, gas consumption & cost of the new controls solution.

Opentherm alone additional savings will likely be in single figures % wise - again depends upon what your existing control system is & how you use it (& assuming that youir boiler is set up properly to condense).

waqasahmed

BUFF said:

probably a daft question but have you contacted Vokera to ask what exactly you need, availability & cost?

whether it is worth it depends upon what your existing control system is & how you use it, gas consumption & cost of the new controls solution.

Opentherm alone additional savings will likely be in single figures % wise - again depends upon what your existing control system is & how you use it (& assuming that youir boiler is set up properly to condense).

Probably not daft given that if it's say £100 or so, it probably isn't that bad as a 5% saving can easily cost more than £100

I'll have a look at that other forum that was recommended. On the flip side, at least this boiler is like 93% efficient. It wouldn't be my first choice but a five year warranty is nice. The last owners of the house put it in, because theirs broke just when they had their house up. I got the house roughly six months later 

Bendy_House

Looking at the link in your first post, wow, I didn't know they were so cheap! It's no great surprise, then, that things like Opentherm interfaces are optional extras.

I don't think all boilers have this option, so that would put the Vokera 'up' there a bit.

From what I understand of Opentherm, it's a more 'delicate' type of temp control. So, unlike most normal systems which are controlled by a room stat, and get the boiler running, at full rate, until that room temp is reached, and then turns the boiler off, and then turns it back on when the temp drops to suit demand, 'Opentherm' instead works out when the desired room temp is being reached, so backs-off the boiler in advance so that it arrives at that temp without any overshoot.

It's a bit like driving up to a road junction - one way is to approach at 30mph and then slam on the brakes when it's reached, and the other is to know the junction is approaching, so to remove throttle and to coast there slowly.

What are your existing controls? Prog stat or just 'manual'?

I'd try and find out just how much more Opentherm could/will save you above normal decent controls like a Hive or Nest, and then make a judgement as to whether it's worth it. For example, if all you currently have is a manual 'dial' room 'stat, then it would be worth upgrading that in any case, so perhaps worth going 'extra' for Opentherm. But, if you already have a good Prog Stat, it might not be worth the extra outlay.

But you need some figures.

waqasahmed

Bendy_House said:

Looking at the link in your first post, wow, I didn't know they were so cheap! It's no great surprise, then, that things like Opentherm interfaces are optional extras.

I don't think all boilers have this option, so that would put the Vokera 'up' there a bit.

From what I understand of Opentherm, it's a more 'delicate' type of temp control. So, unlike most normal systems which are controlled by a room stat, and get the boiler running, at full rate, until that room temp is reached, and then turns the boiler off, and then turns it back on when the temp drops to suit demand, 'Opentherm' instead works out when the desired room temp is being reached, so backs-off the boiler in advance so that it arrives at that temp without any overshoot.

It's a bit like driving up to a road junction - one way is to approach at 30mph and then slam on the brakes when it's reached, and the other is to know the junction is approaching, so to remove throttle and to coast there slowly.

What are your existing controls? Prog stat or just 'manual'?

I'd try and find out just how much more Opentherm could/will save you above normal decent controls like a Hive or Nest, and then make a judgement as to whether it's worth it. For example, if all you currently have is a manual 'dial' room 'stat, then it would be worth upgrading that in any case, so perhaps worth going 'extra' for Opentherm. But, if you already have a good Prog Stat, it might not be worth the extra outlay.

But you need some figures.

So I've currently got no smart TRVs, however I do have the thermostat they've provided

I think it's a traditional thermostat where you can have a timer to put the temp to a certain amount at certain times 

Bendy_House

waqasahmed said:

Bendy_House said:

Looking at the link in your first post, wow, I didn't know they were so cheap! It's no great surprise, then, that things like Opentherm interfaces are optional extras.

I don't think all boilers have this option, so that would put the Vokera 'up' there a bit.

From what I understand of Opentherm, it's a more 'delicate' type of temp control. So, unlike most normal systems which are controlled by a room stat, and get the boiler running, at full rate, until that room temp is reached, and then turns the boiler off, and then turns it back on when the temp drops to suit demand, 'Opentherm' instead works out when the desired room temp is being reached, so backs-off the boiler in advance so that it arrives at that temp without any overshoot.

It's a bit like driving up to a road junction - one way is to approach at 30mph and then slam on the brakes when it's reached, and the other is to know the junction is approaching, so to remove throttle and to coast there slowly.

What are your existing controls? Prog stat or just 'manual'?

I'd try and find out just how much more Opentherm could/will save you above normal decent controls like a Hive or Nest, and then make a judgement as to whether it's worth it. For example, if all you currently have is a manual 'dial' room 'stat, then it would be worth upgrading that in any case, so perhaps worth going 'extra' for Opentherm. But, if you already have a good Prog Stat, it might not be worth the extra outlay.

But you need some figures.

So I've currently got no smart TRVs, however I do have the thermostat they've provided

I think it's a traditional thermostat where you can have a timer to put the temp to a certain amount at certain times 

Photo of current 'stat?

It sounds like a Programmable Thermostat, which would be good. So, I'd suggest you research the possible energy savings to be gained by going Opentherm. It's one of these 'improvements' that you would be happy to fit at boiler installation stage, as the additional cost would be minimal, but perhaps not make sense to REPLACE an otherwise acceptable Prog Stat. 

I don't know enough about them.

FreeBear

Bendy_House said: From what I understand of Opentherm, it's a more 'delicate' type of temp control. So, unlike most normal systems which are controlled by a room stat, and get the boiler running, at full rate, until that room temp is reached, and then turns the boiler off, and then turns it back on when the temp drops to suit demand, 'Opentherm' instead works out when the desired room temp is being reached, so backs-off the boiler in advance so that it arrives at that temp without any overshoot.

OpenTherm is just a bus & communication protocol specification.

The bus specification is point to point over two wires with a maximum length of 50m. Connecting multiple devices to an OpenTherm bus will require a dedicated hub (or devices that can act like a hub).

The communication protocol defines a set number of "messages" along with how the data is passed from (for example) the boiler and the thermostat. The OpenTherm specification does not define how the data is used or any "smart" function on top.

If you want smarter control over your heating system such as outside temperature compensation or predictive boiler run times, you need a smarter boiler or an intelligent control system. OpenTherm just provides a backbone for the two to talk to each other. OpenTherm will not, in its self, save you any money. That will be down to the intelligence of the system and the end user.

Rodders53

https://www.diynot.com/diy/threads/vokera-easi-heat-and-opentherm.523646/

May be a good place to ask if their resident expert is still on there.

Bendy_House

FreeBear said:

Bendy_House said: From what I understand of Opentherm, it's a more 'delicate' type of temp control. So, unlike most normal systems which are controlled by a room stat, and get the boiler running, at full rate, until that room temp is reached, and then turns the boiler off, and then turns it back on when the temp drops to suit demand, 'Opentherm' instead works out when the desired room temp is being reached, so backs-off the boiler in advance so that it arrives at that temp without any overshoot.

OpenTherm is just a bus & communication protocol specification.

The bus specification is point to point over two wires with a maximum length of 50m. Connecting multiple devices to an OpenTherm bus will require a dedicated hub (or devices that can act like a hub).

The communication protocol defines a set number of "messages" along with how the data is passed from (for example) the boiler and the thermostat. The OpenTherm specification does not define how the data is used or any "smart" function on top.

If you want smarter control over your heating system such as outside temperature compensation or predictive boiler run times, you need a smarter boiler or an intelligent control system. OpenTherm just provides a backbone for the two to talk to each other. OpenTherm will not, in its self, save you any money. That will be down to the intelligence of the system and the end user.

What am I confusing it with?!

There's a system where the room stat doesn't just tell the boiler when the temp has been reached, but when it's getting close, and- I think - how quickly. The boiler then modulates in response to it doesn't overshoot, but it also tries to MAINTAIN the desired temp, instead of clicking on and of below and above it.

Summat like that.