Strange flow temperature on Okofen boiler

[FabOko02]

Hi,

I would like to thank Pilpoill who discovered why the boiler behaved like this and who gave me a lot of advice.
Indeed, my boiler went safely because of a bad setting. The maximum temperature of the system was set at 75 ° C instead of 95 ° C as recommended by the manufacturer.
I don't know if it was the installer or the previous owner who set it up like this, but now it's a thing of the past.

Several parameters were adjusted as well as the circulators which were not set correctly either.

Thanks again,

[Pilpoill]

I struggled at the beginning of my own installation a few years ago, normal that I help in my turn

Have a good heating season and thank you for your feedback!

[ArthurD]

Hello Pilpoil and FabOko02,

I am new to the forum and concretely, I have a lot of trouble optimizing my Pellematic (I have no problems with the temperature in the house).

I seem to have the same problem with a PE1 t medium burner at 15 min...
Is it possible to know exactly what settings have been made?

PE adjustment screenshot

Screenshot 2023-11-16 093605.png (32.84 KiB) Viewed 955 times

Was the cut-off temperature changed?

Thank you in advance for your help,

[Pilpoill]

Hello ArthurD,

For my part, it would be more interesting to see the overall operation using the curves to give you what is normal or weird.
If your boiler is connected, I can possibly help you with all this.

Already in what I see this 15K is to be avoided because your boiler will restart much too late and therefore - without seeing the slightest curve - I am almost sure that it will go back below 60°C minimum.
The value of 10K is the classic value.

[ArthurD]

Hello Pilpoill,

Here are the curves:

Graph_20231116 (4).png (198.34 KiB) Viewed 936 times

And the settings of the radiator heating circuit:

Slope: 1,4
Curve foot: 35°C
Lim T ext comfort: 22 °C
Lim T ext reduced: 20 °C
Anticipation duration: 180,0 min
Smoothing: 10 min
Amb. probe influence : 10,0
Ambient T Hysteresis off: 1,0 K
Ambient T Hysteresis on: 1,0 K

Thank you for your help.

PS: I modified to 10K on your advice

[Pilpoill]

The 10K is for the boiler operating hysteresis and I was therefore right for the T°

For the influence of the room sensor, if radiators, the value of 5 is recommended.

I don't see an external temperature and your heating range is permanent at a setpoint slightly lower than 20°C.
Is this a voluntary choice?

There is perhaps the power to be adapted but first you need to know the precise model of boiler (silver-colored nameplate normally stuck behind the boiler), the surface to be heated, the level of insulation, your region, if it does the ECS or not, any particularities.

[ArthurD]

Hehe so responsive! THANKS

With the modification, I have a higher heat:

Graph_20231116 (6).png (209.66 KiB) Viewed 917 times

I have a Pellematic Compact PES 218 model power: 5 to 18 KW (which seems set at 18kW)

I currently have 150m² (development in progress so it increases as the work progresses) in the south of Normandy to heat
on 2 levels of 2m50
insulated with 28cm of cellulose wadding for the roof
10cm of fiberglass for the walls (no floor insulation)
all with double glazing and a single hygro flow VMC.

I had calculated and carried out a thermal study with a relative which gave:
Total losses: 11558 W
Relaunch overpower: 1570 W
Total power to install: 13128 W

The DHW is produced in separate electricity.

Concerning the setpoint, I set it at 19,5°C arbitrarily so as not to have a change in behavior during the calibration phase.

[Pilpoill]

Could you show the outside temperature on your graph?

With the 10K of the boiler part, it restarts earlier which prevents it from going up to 100% to produce so little and the v3v no longer has to be ordered when closing as before...
For me it actually seems far too powerful compared to your calculated needs of 13kW.

If your Compact was delivered in 18 (on its nameplate) and your installer did not intervene in the heat exchangers, you can upgrade it to 16kW.
After the winter and depending on what your curves will look like at the coldest, I will advise you - or not - to ask your installer to reduce the power but to go <16kW you also have to intervene at the heart of the beast.

PS: most installers and technicians absolutely do not see it the same way as the customer…

[sicetaitsimple]

@Christophe my private messages remain in my outbox. I can't even contact you through the forum while the javascript option is set to True in my browser.
Could you intervene?

It seems to me (not certain) that a PM "remains" visible in the outbox until the recipient opens it.

[Pilpoill]

It seems to me (not certain) that a PM "remains" visible in the outbox until the recipient opens it.

Thank you, this is indeed what happened because it is still in the outbox for a member who has not reconnected since.

All other PMs have disappeared from the outbox and been answered, so you can be sure