Vaillant EcoTec Sustain 28, sensoComfort RF and sensoNET

[KNCowans]

Hello all

I hope you are well.

I had a Vaillant EcoTec Sustain 28 Installed in January 2022 under the Eco Scheme.

I only had a Choice of Manufacturer, I chose Vaillant, however, I did not have any say in the Model or Kw Rating of the Boiler, that was left to the Eco Scheme and the Installers.

It is oversized for my System and is Down Rated to 8kw as I only have 6 Radiators, all P+ which come to a Total of 6.39kw

At the Time I had Hive Controls including the Hive TRVs which were carried over from the previous Boiler as I was not in the position to Upgrade the Controls.

Now, I am looking at replacing the Hive Controls with the Vaillant sensoComfort RF including the Wireless Weather Sensor, Vaillant sensoNET and 6 x Vaillant AmbiSense TRVs.

Once this has been Installed, hopefully Next Week, are there any Settings that I need to be aware of?

Thanks in advance

Kevin

 

[KNCowans]

Hello all

Well, everything is Installed and Working as it should.

Regarding the Heat Curve, it is currently Set at 1.2 which picked up during Installation and the House is Slow getting to Temperature.

The Adaptive Heat Curve is Enabled.

Does anyone know how long it takes for the Adaptive Heat Curve to Adjust?

Thanks in advance

Kevin

 

[Harry Bloomfield]

Does anyone know how long it takes for the Adaptive Heat Curve to Adjust?

My understanding, is that it will continually readjust itself.

 

[Johntheo5]

Hello all

Well, everything is Installed and Working as it should.

Regarding the Heat Curve, it is currently Set at 1.2 which picked up during Installation and the House is Slow getting to Temperature.

The Adaptive Heat Curve is Enabled.

Does anyone know how long it takes for the Adaptive Heat Curve to Adjust?

Thanks in advance

Kevin

If its this set of curves then by knowing the outside temperature and looking at the actual target temperature you can see if its adaptive or not. If the outside temperature just now is 10C then the unadapted target temperature is ~ 38C (1.2 curve) and so on. If the rated output of your rads are 6.39kw then they will only emit ~1.55kw at a flowtemperature of 38C, (return, 35C) so your boiler might never even get up to 38C, is it firing on/off continuously?.

 

[KNCowans]

Hello

Thanks for the Replies.

The Boiler does not Cycle continuously and works well, thankfully.

With the sensoComfort Adaptive Heat Curve Enabled, do you happen to know if there is a Learning Period?

The sensoComfort was only Installed Yesterday Afternoon so I am assuming that there may be a Delay before the Heat Curve starts to be adjusted.

I am hesitant to Adjust the Heat Curve Manually, increasing it from 1.2, in case it interferes with the Adaptive Heat Curve Setting.

Thanks

Kevin

 

[Johntheo5]

As I said Kevin, measure the outside temperature, go to the WC curves (if like above), go vertically upwards from the ambient temperature reading until it hits the 1.2 curve, the set target temperature is horizontally to the left (Y axis).
What is the outside air temperature just now and what is the boiler flow temperature?

I have no idea how long it takes to adapt.

 

[KNCowans]

Hello

Sorry, I misunderstood.

I have the Wireless Weather Sensor connected to the sensoComfort which Reports the Outside Temperature as being 11.5⁰C.

The Current Flow Temperature is 40⁰C (ish).

All of the Rooms except one are upto Temperature (20⁰C) after approximately 4.5 Hours.

increasing the Heat Curve would presumably Help.

Thanks

Kevin

 

[Johntheo5]

Hello

Sorry, I misunderstood.

I have the Wireless Weather Sensor connected to the sensoComfort which Reports the Outside Temperature as being 11.5⁰C.

The Current Flow Temperature is 40⁰C (ish).

All of the Rooms except one are upto Temperature (20⁰C) after approximately 4.5 Hours.

increasing the Heat Curve would presumably Help.

Thanks

Kevin

11.5C OT = 37.5C target temp so it may have made some adjustment.
Something strange here though, at a boiler/rad flow temperature of 40C the rads will emit 27.7% of their rated (T50) output, the 28kw Vaillant Sustain has a minimum output of ~ 7.5kw, its not cycling, so the installed rated output of your rads must be ~ 27kw to enable the boiler to run continuously at its minimum output, yet you have only 6 rads?

 

[KNCowans]

Hello

Sorry, when i said that the Boiler was not continually Cycling I meant that it does Cycle but not all the Time, hopefully that makes sense.

Also, the ecoTec Sustain is 28kw but has 19kw for Heating.

Thanks

Kevin

 

[Johntheo5]

Yes, I saw that but its minimum output is 7.5kw, you say " I only have 6 Radiators, all P+ which come to a Total of 6.39kw" so at ~ 40C flow temperature the boiler (on CH only) will have to be cycling very frequently as the demand is only ~ 1.8kw, based on that rated rad output, the target temp wold have to be > 70C to enable the boiler to stay firing for most of the time but that corresponds to a outside temp of minus 20C or even less.
What does P+ mean, above?.

 

[KNCowans]

Hello

The P+ refers to the Radiator Type, 2 Panel one Set of Fins.

I do not understand why the Boiler is not Cycling more frequently, all I can tell you is what I see, sorry.

Thanks

Kevin