Hi Egon,
I think your installation is a little more complicated, than first thinking.
First of all, I am not sure if your burner size is correct (24 KW) it looks a little too big.
It sounds like the burner has never been fine tuned.
Definitely you need a “drag stabilizer” in your chimney.
The most critical points in selecting and installing pellet burners are:
• Choose a burner with just only enough power, don’t oversize.
• Always keep the burners power as low as possible.
• Make sure to have a stable, low drag in the chimney (vacuum aprox. -10 Pa.).
• Adjust to proper combustion.
These points must be looked after by the installer of the system.
Afterwards the user only needs to assure that the burner and boiler are kept clean, and the combustion is checked and adjusted if necessary.
In your case it sounds like the burner is chosen not to be too little, it is installed without drag stabilizer, and it might need to have the combustion proper adjusted.
I do not know who made the installation, and this is not an indictment of him, but merely a statement of what should be done.
So Egon, it is all up to you to decide if you want to go further or just leave it as it is.
I would recommend you to the following:
• Install a drag stabilizer in your chimney.
• Readjust burner parameters for chimney drag.
• Readjust burner parameters for combustion (Auger time low and high).
I can see from your web-page that you properly have an Ouman EH-203 regulator on your installation.
If this is correct, this regulator can be the reason to some of the strange curves from your burner, but your installation still needs to be correct done.
To be honest, I don’t understand why use such a sophisticated regulator as Ouman EH-203, and let the burner work in an unoptimized way.
You could save a lot of money in proper combustion in your burner.
Best regards
Michael
