Ideal Vogue & Opentherm via Honeywell T6 Lyric (wired version)

[richardc1983]

Great support from Idea; NOT

Hi Richard



Sorry to hear that the PCB did not remedy the fault. The problem clearly must lie externally to the boiler as we first initially thought.

I wish you good luck with getting the issue resolved.





Paul Griffith

Installer Support Team

Tel: +44(0)1482 498663

https://www.idealboilers.com

[richardc1983]

Disgraceful how someone can just wash their hands of it, whats point in selling opentherm if its not gonna do as advertised.

[richardc1983]

My response to Ideal:

"I think your tech guys need to talk to Honeywell. This isn't down to me to resolve as a member of the public.

No good passing the blame to each other you guys need to communicate."

[richardc1983]

Still waiting for Honeywell or Ideal to come back to me regarding where the issues lay. Seems they have washed their hands of it!

[paulockenden]

Well Ideal is still publicly saying that it works: https://twitter.com/ideal_heating/st...05115006021632

[richardc1983]

Well Ideal is still publicly saying that it works: https://twitter.com/ideal_heating/st...05115006021632

Thanks for sharing! I have quickly responded to that!

[GrahamW]

Hi Paul, You seem to be au-fait with the Ideal Vogue boiler and Opentherm, I have started a new thread (Ideal Vogue using Opentherm to set pump speed or modify Pump Modulation to minimum) in the hope that you would have some advice.

Graham

[richardc1983]

Hi Paul, You seem to be au-fait with the Ideal Vogue boiler and Opentherm, I have started a new thread (Ideal Vogue using Opentherm to set pump speed or modify Pump Modulation to minimum) in the hope that you would have some advice.

Graham

Well here we are again near the heating season and notice the heating is coming on in a morning now. Noticing further control issues and the Lyric T6 controller. So frustrating as each blame each other and I think this issue is on honeywell's side. The boiler is coming on in a morning, ramps upto 48C flow temp which is the max boiler flow temp I have set it to, room temp quickly reaches this within half an hour, but boiler then constantly cycles on and off burner coming on for about 30 seconds a time... having looked into this further with Ideal who sent an engineer they are blaming the lyric as requesting too high a flow temp. For example the boiler will cycle off, then the flow temp will drop to say 32C rather than the lyric then switching the burner back on and requesting a low flow temp to keep it ticking over as the room temp set temp of 21C (actual room temp reported by the lyric is 20C) it seems to request a flow temp of 42C, the burner comes on full pelt and doesn't seem to be able to react or slow down quickly enough so then overshoots and we end up with a flow temp of 46C the burner then goes off as soon as this happens the flow temp drops within seconds back to about 32/33C causing the burner to fire back up again for a 30s blast.

Ideal visited and checked thermistors on the boiler, they also set it to "service mode minimum fire rate" which fires the boiler up in the minimum rate to maintain a flow temp of 30C (the minimum flow temp setting on this boiler) and guess what in this mode the burner stays on for as long as required providing a nice low flow temp of 30C. For this reason Ideal are blaming it on the Lyric T6 for requesting the burner fire up too high and because the heat is not being lost from the system quick enough due to flow temp being too high this causes the burner to cycle off.

With this constant cycling - radiators are not at an even temperature and the overall flow temp is running at about 32/33C even though the lyric is asking for 42C. It seems to be firing the boiler too high and we have proved via Ideal that the boiler is capable of coming on low and maintaining a flow temp of 30C, it seems the lyric is ramping the boiler burner up at burner on cycle then trying to bring the temp back down but by this point the flow has already exceeded the "control flow temp" that the lyric is asking for so the burner goes off.

This makes no difference whether low load control is turned off in the lyric or not. Honeywell don't seem to be picking up the phone either as there phone message says they have an emergency.

The app is poor also, I set it the other night to 21C, the house was at 19C. Seconds later the app had reverted the temp back to the set back temp of 16C so the heating wouldn't come on, it was not my connection either as I could connect to the thermostat and amend timers. I have asked honeywell if there is a firmware update released to rectify these poor control issues as Ideal say that the opentherm is what tells the boiler what to do, the boiler only jumps in via its safety devices etc.

For all those who are considering this combination, I would avoid as I think the lyric is too new, the whole idea of opentherm is a good one, but unfortunetly someone needs to own it as it takes control over the boiler so according to ideal the boiler is only responding to instruction and they have confirmed the boiler is able to start up at the minimum rate and supply just 30C so why cant it supply 42C without massively overshooting. This cycling on and off is very poor and wasteful of gas for it to be coming on too high.

[The EVOHOME Shop]

Richard the controls request the flow temperature from the boiler via OpenTherm, but they don't control how that happens as this is the 'slaves' (boilers) job. I have exactly the same setup on an Intergas Rapid and it works just as I expect it to.

When the boiler has a low flow temp requested from the controls, unless the low end modulation of the boiler is good enough or there are additional settings on the boiler to slowly increase boiler output based on demand (Intergas has this) to remain below the required output then the boilers burner will 'cycle' and the pump will run. How the boiler handles the requested 'control setpoint' is completely up to the boiler - not the controls.

I personally think you are misunderstanding how OpenTherm works and the guys at Ideal certainly don't know how OpenTherm is supposed to work by the sounds of it.

[richardc1983]

Thanks for the reply, this cycling occurs as the boiler seems to ramp up too quickly, if I put the boiler into “service mode minimum output” this starts the burners at the minimum output so no overshooting occurs so ideal need to explain why this doesn’t occur during normal operation rather than passing the blame. Totally understand how open therm works as it’s very similar to how inverter air conditioning control strategy works based on demand and air temperature. However inverter air con also takes into account the refrigerant temps to calculate the load.

Richard the controls request the flow temperature from the boiler via OpenTherm, but they don't control how that happens as this is the 'slaves' (boilers) job. I have exactly the same setup on an Intergas Rapid and it works just as I expect it to.

When the boiler has a low flow temp requested from the controls, unless the low end modulation of the boiler is good enough or there are additional settings on the boiler to slowly increase boiler output based on demand (Intergas has this) to remain below the required output then the boilers burner will 'cycle' and the pump will run. How the boiler handles the requested 'control setpoint' is completely up to the boiler - not the controls.

I personally think you are misunderstanding how OpenTherm works and the guys at Ideal certainly don't know how OpenTherm is supposed to work by the sounds of it.

[The EVOHOME Shop]

That's fine then, if you understand how OpenTherm works then you understand that this is a boiler issue? The fact that Ideal have programmed the boiler to go to maximum and then modulate down is one issue. The heat produced by the burner has to get away from the heat exchanger at a set flow rate at a given output, otherwise the heat exchanger gets too hot and will turn off the burner. As the pump is linked to the burner the more heat the burner produces the faster the pump runs, but just because the pump is running faster doesn't mean that the heat has somewhere to go if the flow rate is 'hindered' by something.

Lots going on here mate, but the fact remains the OpenTherm controls tell the boiler the 'control setpoint', the boiler gets to the 'control setpoint' temperature how it sees fit and the heating system governs how much flow comes out of the boilers heat exchanger. Its either the boiler, boiler pump settings or the heating circuit...

[richardc1983]

Makes a lot of sense and is the same way in how I am thinking - ideal have really ****ed up with a control strategy like this. As I mentioned when it is set manually to the minimum burn rate works fine - it should increase gradually not by going full pelt.

I have the pump modulation set to the lowest so the pump runs at 90% all the time as it was even worse when it was modulating between that and 50%.

[The EVOHOME Shop]

As I mentioned when it is set manually to the minimum burn rate works fine - it should increase gradually not by going full pelt.

I have the pump modulation set to the lowest so the pump runs at 90% all the time as it was even worse when it was modulating between that and 50%.

Of course when the burner is set to minimum the boiler won't overheat if the pump speed exceeds the flow rate required to get the heat away from the heat exchanger? Are you sure you don't have the pump speed or settings wrong?

I don't know Ideal boilers, but based on my experience and now what I have learnt over the past 3 months, I know Dutch boilers are by far the best to use with OpenTherm. I walk into a perfectly controlled testing facility each morning...

[Dan_Robinson]

Shouldn't you be walking to Kingswinford by now?

[The EVOHOME Shop]

Shouldn't you be walking to Kingswinford by now?

I will be setting off shortly!