Ökofen, burner start and closing V3V

[tautin25]

Hello everybody
I have an Okofen Pellematic 15kW with the new white regulation V1.15M and a boiler automat CMP2.33. The boiler is installed from 2008 replacing an oil boiler on a heated floor.
I have long observed the operation to refine the rough settings originally made by the installer. I recorded all my observations and consumption history on my site http://granuleconso.free.fr

This subject concerns the very specific behavior of the lighting of a wood fire (pellets). In fact, in contrast to the combustion of gas and fuel oil, which start and stop instantly, wood combustion goes through an ignition and extinguishing phase at each cycle. On ignition the burner takes several minutes before reaching its maximum power. As the boiler is still in use, the temperature may fall below the minimum value triggering the closing of the V3V AND the simultaneous shutdown of the pump. This phenomenon is amplified during a cold period when the boiler is in high demand. It can lead to oscillation phenomena with opening and closing of the V3V.

I observed this behavior on my installation and managed to delete it with the temperature settings below.

The parameters concerned are T min hot 63.0 ° and T lim pump 60.0 ° which allow to separate the ignition of the burner and closing the V3V. T min hot triggers ignition of the burner while T lim pump protects the boiler from cold returns by stopping the pump and closing the V3V. Another parameter of the boiler controller T min hot (p281) can also cause the closing of the V3V. This factory setting at 60.0 ° must not be changed.

I tested the settings by inverting Tmin hot to 60.0 ° and Tmin pump to 63.0 ° and then observed a complete cycle. The boiler was stopped at 57 °: ignition on demand heating regulation with T.chaud cons to 74.0 ° (hot T min + boiler ++ is 60 + 14)
After boiler shutdown at 74.0 ° the temperature goes down, passes 63.0 ° without any action, the pump continues to run and the V3V remains open
The boiler restarts at 60.0 °, the temperature continues to descend towards 59.2 ° before rising again. No valve closing or pump shutdown that occurs only at 59.0 ° (there is a hysteresis of 1.0 °).

What do you think about these observations and what is your approach on this topic

[Did67]

Goods.

I have the same problem. But the regul gray TEM: the problem is insoluble ...

I hesitate to buy a white regul. But you make me hesitate (in the sense of a purchase)!

[manet42]

Hello, Last year with the versionV1 15 M, I had big problems of lowering with the reduced. It has been replaced by a V2.23M which is better.
TAUTIN 25 do you have the same problems?
Goods.

JC

[zefred72]

So what works in one case does not work in the other?
If T min hot = 63.0 ° and T lim pump = 60.0 ° the V3V and the pump stop under 60 °
If T min hot = 60.0 ° and T lim pump = 63.0 ° the V3V and the pump do not stop under 63 °
How to explain this phenomenon ?

[roy1361]

Hello everybody

I will not interfere with your technical discussions on Okofen because I do not own this brand.

However, the operation of my boiler is relatively similar, to such an extent that I had the same lowering phenomenon in the event of sudden strong needs, such as resuming heating to "day temperature" early in the morning.

My machine does not close the V3V, but just cut the circulation pumps the time needed to raise the temperature of the boiler (2 to 3 minutes, without affecting a feeling of comfort inside)

I solved the problem by increasing the difference between the stop temperature and the restart temperature (like tautin25), but also, and this is what I wanted to come about, by programming the charging times of the water tank. 'DHW so that said recharge does not occur during the first two hours of "day heating".
The boiler can thus only take care of the heating of the heating floors and the radiator circuit, and stabilize quickly ...

Thus, I have completely eliminated the oscillations at the start of heating and the "over-lowering" of the boiler temperature ...

Greetings.

[dedeleco]

If not indiscreet, what brand of boiler ???? roy1361 ??

[tautin25]

Last year with the version V1 15 M, I had big problems of lowering with the reduced. It has been replaced by a V2.23M which is better.
TAUTIN 25 do you have the same problems?

The lowering of temperature was indeed not very effective but I do not know what to attribute this phenomenon. Bad algorithm in the regul or very strong inertia of my house (insulating brick walls 42 cm + 80 8 years heating floor cm thick)?
Since this year, I installed a room sensor that gives me a much better responsiveness. T 21.5 °, T cons reduces 20.5 °, hysteresis stop 1.0 °, start hysteresis 1.0 ° not adjustable.
The behavior is different, when switching to reduced the regulator cuts the heating (if not too cold) and the temperature drops faster but the inertia makes that I lose only 2 ° during the night in total stop with about 0 ° outside. The regul only restarts at 19.5 °.
My instructions for 21.5 ° and 20.5 ° may make you think that I'm heating up, but you should know that the best consumer thermometers have a precision of 2 to 2.5 °. The actual temperature may be lower.

What is the way from V1.15M to V2.23M, program change or change of regulation?
How much does it cost ?

[manet42]

Well, that confirms my assumptions.
Last year, I was doing like you to get by with the int probe. and hysteresis. Otherwise it was necessary to ask 12 ° in reduced to have 17 ° / 18 ° ... and in case of cut..le cold
Okofen has changed the regulation under warranty.
Here's what I think about it, posted on the slow motion post. There we are not on the good ...! Never mind.

https://www.econologie.info/share/partag ... I5zF8P.pdf

[tomgey]

I just watched myself too. I have the 2.25 version of the white regulator.
With Tlim pump at 63 ° C and Tmin hot at 60 ° C: nothing happens at 63 ° (the pump works, V3V open). At 60 the boiler restarts. A little below 60 (around 59,5 ° C) the pump stops and the V3V closes. Nadir boiler temp at 57 ° C, it goes back up, the pump restarts at 60 ° C.
It's late afternoon when the house is in balance. But in the morning I actually have more oscillations with radiators which warm up then heat up ... etc
I haven't tried it yet by reversing the settings

[zefred72]

This problem of poor temperature reduction in reduced mode seems to be general (I have the white regulator version 2.18M)

Comfort 19 °
foot 35 °
Slope 1,5
Departure temperature (at 0 ° ext) 55 °
Tamb observed: 18,5 to 19 °

Reduced 14 ° (initially I wanted 16 °)
foot 35 °
Slope 1,5
Departure temperature (at 0 ° ext) 42,5 °
Tamb observed: at the lowest 16,9 °